NRLF 


TUDIES 
OF  TREES 


I 


!ii 


I! 


Date 


PERSONAL  LIBRARY 
OF 

JOHN  WM.    GREGG 

Value 


THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 

Landscape  Architecture 
GIFT  OF 

Professor 
John  Ifon.  Gregg 


Frontispiece. 


:Come  forth  into  the  light  of  things, 
Let  Nature  be  your  Teacher." 

— WORDSWORTH. 


STUDIES  OF  TREES 


BY 


J.  J.^LEVISON,  M.F. 

Lecturer  on  Ornamental  and  Shade  Trees,  Yale  University  Forest 

School;  Forester  to  the  Department  of  Parks, 

Brooklyn,  2f.  Y. 


FIRST   EDITION 

FIRST    THOUSAND 


NEW  YORK 

JOHN  WILEY  &  SONS,  INC. 

LONDON:  CHAPMAN  &  HALL,  LIMITED 

1914 


Copyright,  1914 

BY 

J.  J.   LEVISON 


Add!l 

LANDSCAPE 
ARCHJTCCTUfiE 

GIFT 


THE  SCIENTIFIC   PRESS 

ROBERT   DRUMMOND    AND  COMPANY 

BROOKLYN,  IN.   Y. 


ARCH- 

PREFACE 


IN  presenting  this  volume,  the  author  is  aware  that  there 
are  several  excellent  books,  dealing  with  one  phase  or  another 
of  tree  life,  already  before  the  public.  It  is  believed,  how- 
ever, that  there  is  still  need  for  an  all-round  book,  adapted 
to  the  beginner,  which  gives  in  a  brief  and  not  too  technical 
way  the  most  important  facts  concerning  the  identification, 
structure  and  uses  of  our  more  common  trees,  and  which 
considers  their  habits,  enemies  and  care  both  when  grow- 
ing alone  and  when  growing  in  groups  or  forests. 

In  the  chapters  on  the  identification  of  trees,  the  aim 
has  been  to  bring  before  the  student  only  such  characters 
and  facts  as  shall  help  him  to  distinguish  the  tree  readily 
during  all  seasons  of  the  year.  Special  stress  is  laid  in  each 
case  on  the  most  striking  peculiarities.  Possible  confusion 
with  other  trees  of  similar  appearance  is  prevented  as  far 
as  possible  through  comparisons  with  trees  of  like  form  or 
habit. 

Only  such  information  is  given  concerning  the  structure 
and  requirements  of  trees  as  will  enable  the  reader  better 
to  understand  the  subsequent  chapters.  In  the  second  half 
of  the  book,  practical  application  is  made  of  the  student's 
general  knowledge  thus  acquired,  and  he  is  acquainted  with 
the  fundamental  principles  of  planting,  care,  forestry,  wood 
identification  and  nature  study. 

The  author  recognizes  the  vastness  of  the  field  he  is 
attempting  to  cover  and  the  impossibility  of  even  touching, 


734 


vi  PREFACE 

in  a  small  hand-book  of  this  character,  on  every  phase  of 
tree  study.  He  presumes  no  further;  yet  he  hopes  that 
by  adhering  to  what  is  salient  and  by  eliminating  the  less 
important,  though  possibly  interesting,  facts,  he  is  able 
to  offer  a  general  and  elementary  resume  of  the  whole 
subject  of  value  to  students,  private  owners,  farmers 
and  teachers. 

In  the  preparation  of  Chapter  VIII  on  "  Our  Common 
Woods:  Their  Identification,  Properties  and  Uses,"  con- 
siderable aid  has  been  received  from  Prof.  Samuel  J.  Record, 
author  of  "  Economic  Woods  of  the  United  States." 
Acknowledgment  is  also  due  to  the  U.  S.  Forest  Service  for 
the  photographs  used  in  Figs.  18,  122  to  138  inclusive  and 
142;  to  Dr.  George  B.  Sudworth,  Dendrologist  of  the  U.  S. 
Forest  Service,  for  checking  up  the  nomenclature  in  the 
lists  of  trees  under  Chapter  V;  to  Dr.  E.  P.  Felt,  Entomol- 
ogist of  the  State  of  New  York,  for  suggestions  in  the 
preparation  of  the  section  of  the  book  relating  to  insects; 
to  Dr.  W.  A.  Murrill,  Assistant  Director  of  the  New  York 
Botanical  Gardens,  for  Fig.  108;  and  to  Mr.  Hermann 
W.  Merkel,  Chief  Forester  of  the  New  York  Zoological 
Park,  for  Figs.  26,  59  and  60. 

J.  J.  LEVISON. 

BROOKLYN.  N.  Y. 
June,  1914. 


CONTENTS 


CHAPTER   I 

PAGE 

How  TO  IDENTIFY  TREES 1 

The  Pines 2 

The  Spruce  and  Hemlock 11 

The  Red  Cedar  and  Arbor- vitse 19 

CHAPTER  II 

How  TO  IDENTIFY  TREES  (Continued} 25 

The  Larch  and  Cypress 25 

The  Horsechestnut,  Ash,  and  Maple 31 

Trees  Told  by  their  Form 46 

Trees  Told  by  their  Bark  or  Trunk 59 

The  Oaks  and  Chestnut 71 

CHAPTER  III 

How  TO  IDENTIFY  TREES  (Continued} 83 

The  Hickories,  Walnut,  and  Butternut 83 

Tulip  Tree,  Sweet  Gum,  Linden,  Magnolia,  Locust,  Catalpa, 

Dogwood,  Mulberry,  and  Osage  Orange 90 

CHAPTER   IV 

THE  STRUCTURE  AND  REQUIREMENTS  OF  TREES 106 

vii 


viii  CONTENTS 

CHAPTER  V 

PAGE 

WHAT  TREES  TO  PLANT  AND  How 119 

Trees  for  the  Lawn 1 19 

Trees  for  the  Street 123 

Trees  for  Woodland 126 

Trees  for  Screening 128 

CHAPTER  VI 

THE  CARE  OF  TREES 134 

Insects  Injurious  to  Trees  and  How  to  Combat  Them 134 

Important  Insects 141 

Tree  Diseases 153 

Pruning  Trees 160 

Tree  Repair , 168 

CHAPTER  VII 

FORESTRY 179 

What  Forestry  Is  and  What  It  Does 179 

Care  of  the  Woodland 203 

CHAPTER  VIII 

OUR  COMMON  WOODS:   THEIR  IDENTIFICATION,  PROPERTIES  AND 

USES 217 

Woods  Without  Pores  (Soft  woods) 224 

Woods  with  Pores  (Hard  woods) 226 

CHAPTER  IX 
AN  OUTDOOR  LESSON  ON  TREES 234 


ERRATA 


Pages  1,  11,  13,  17,  25,  26,  and  31,  for  leaflets  read  leaves. 

Page  19,  lines  17  and  18  from  top,  page  29,  line  19  from  top,  and 

page  30,  line  2  from  top,  for  leaves  read  twigs. 

Page  23,  the  paragraph  under  Leaf  should  read:    "  Leaves   of  two 

kinds,  one  scale-like  and  flat,  the  other  keeled,  all  tightly  pressed  to 

the  twig  (see  Fig.  13)." 

Page  29,  line  2  from  top,  for  half  an  inch  read  one  inch. 
Page  38,  line  4  from  top,  for  terminal  twigs  read  tips  of  the  twigs- 
Page  55,  last  line  should  read:    "Leaf:    Like  that  of  a  leaflet  of 

maidenhair  fern,  Fig.  45." 

Page  90,  line  4  from  bottom,  for  an  inch  read   three-quarters   of 

an  inch. 

Page  91,  line  2  from  top,  for  flower  read  fruit. 

Page  100,  paragraph  "Distinguishing  characters,"  under  "Black 

Locust"  should   read:    "The  bark  of  the  trunk  is  rough  and  deeply 

ridged,  as  shown  in  Fig.  81.     The  buds  are  hardly  noticeable;  the 

twigs  sometimes  bear  small  spines  on  one  side.     The  leaves  are  large, 

compound,    and   fern-like.     The    individual    leaflets    are    small    and 

delicate." 


INTRODUCTION 


A  GOOD  many  popular  books  on  trees  have  been  published 
in  the  United  States  in  recent  years.  The  continually 
increasing  demand  for  books  of  this  character  indicates  the 
growing  public  interest  not  only  in  the  trees  that  we  pass 
in  our  daily  walks,  but  also  in  the  forest  considered  as  a 
community  of  trees,  because  of  its  aesthetic  and  protective 
value  and  its  usefulness  as  a  source  of  important  economic 
products. 

As  a  nation,  we  are  thinking  more  about  trees  and  woods 
than  we  were  wont  to  do  in  the  years  gone  by.  We  are 
growing  to  love  the  trees  and  forests  as  we  turn  more  and 
more  to  outdoor  life  for  recreation  and  sport.  In  our 
ramblings  along  shady  streets,  through  grassy  parks,  over 
wooded  valleys,  and  in  mountain  wildernesses  we  find 
that  much  more  than  formerly  we  are  asking  ourselves  what 
are  these  trees  what  are  the  leaf,  flower,  twig,  wood  and  habit 
characteristics  which  distinguish  them  from  other  trees; 
how  large  do  they  grow;  under  what  conditions  of  soil  and 
climate  do  they  thrive  best;  what  are  their  enemies  and  how 
can  they  be  overcome;  what  is  their  value  for  wood  and  other 
useful  products ;  what  is  their  protective  value ;  are  they  use- 
ful for  planting  along  streets  and  in  parks  and  in  regenerat- 
ing forests;  how  can  the  trees  of  our  streets  and  lawns  be 
preserved  and  repaired  as  they  begin  to  fail  from  old  age 

ix 


x  INTRODUCTION 

or  other  causes?  All  these  questions  and  many  more  relat- 
ing to  the  important  native  and  exotic  trees  commonly 
found  in  the  states  east  of  the  Great  Lakes  and  north  of 
Maryland  Mr.  Levison  has  briefly  answered  in  this  book. 
The  author's  training  as  a  forester  and  his  experience  as 
a  professional  arboriculturist  has  peculiarly  fitted  him  to 
speak  in  an  authoritative  and  interesting  way  about  trees 
and  woods. 

The  value  of  this  book  is  not  in  new  knowledge,  but  in 
the  simple  statement  of  the  most  important  facts  relating 
to  some  of  our  common  trees,  individually  and  collectively 
considered.  A  knowledge  of  trees  and  forests  adds  vastly 
to  the  pleasures  of  outdoor  life.  The  more  we  study  trees 
and  the  more  intimate  our  knowledge  of  the  forest  as  a  unit 
of  vegetation  in  which  each  tree,  each  flower,  each  animal  and 
insect  has  its  part  to  play  in  the  complete  structure,  the 
greater  will  be  our  admiration  of  the  wonderful  beauty  and 
variety  exhibited  in  the  trees  and  woods  about  us. 

J.  W.  TOUMEY, 

Director,  Yale  University  Forest  School. 
NEW  HAVEN,  CONN., 
June,  1914. 


STUDIES   OF   TREES 


CHAPTER  I 
HOW  TO  IDENTIFY  TREES 

THERE  are  many  ways  in  which  the  problem  of  identi- 
fying trees  may  be  approached.  The  majority  attempt 
to  recognize  trees  by  their  leaf  characters.  Leaf  charac- 
ters, however,  do  not  differentiate  the  trees  during  the  other 
half  of  the  year  when  they  are  bare.  In  this  chapter  the 
characterizations  are  based,  as  far  as  possible,  on  peculiarities 
that  are  evident  all  year  round.  In  almost  every  tree  there 
is  some  one  trait  that  marks  its  individuality  and  separates 
it,  at  a  glance,  from  all  other  trees.  It  may  be  the  general 
form  of  the  tree,  its  mode  of  branching,  bark,  bud  or  fruit. 
It  may  be  some  variation  in  color,  or,  in  case  of  the  ever- 
green trees,  it  may  be  the  number  and  position  of  the 
needles  or  leaflets.  The  species  included  in  the  following 
pages  have  thus  been  arranged  in  groups  based  on  these 
permanent  characters.  The  individual  species  are  further 
described  by  a  distinguishing  paragraph  in  which  the 
main  character  of  the  tree  is  emphasized  in  heavy  type. 

The  last  paragraph  under  each  species  is  also  important 
because  it  classifies  all  related  species  and  distinguishes 
those  that  are  liable  to  be  confused  with  the  particular 
tree  under  consideration. 


STUDIES  OF  TREES 


GROUP  I.     THE  PINES 

How  to  tell  them  from  other  trees:    The  pines  belong 
to  the  coniferous  class  of  trees;    that  is,  trees  which  bear 


FIG.  1. — Twig  of  the  Austrian  Pine. 

cones.     The  pines  may  be  told  from  the  other  coniferous 
trees  by  their  leaves,  which  are  in  the  form  of  needles  two 


THE  PINES 


IL 


inches  or  more 
in  length.  These 
needles  keep 
green  throughout 
the  entire  year. 
This  is  character- 
istic of  all  conif- 
erous trees,  ex- 
cept the  larch  and 


Twig  of  the 
White  Pine. 


cypress,  which  shed 
their  leaves  in  winter. 
The  pines  are  widely 
distributed  through- 
out the  Northern 
Hemisphere,  and  in- 
clude about  80  dis- 
tinct species  with  over 
600  varieties.  The 
species  enumerated 

here  are  especially  common  in  the  eastern  part  of  the  United 
States,  growing  either  native  in  the  forest  or  under  cul- 


4  STUDIES  OF  TREES 

tivation  in  the  parks.  The  pines  form  a  very  important 
class  of  timber  trees,  and  produce  beautiful  effects  when 
planted  in  groups  in  the  parks. 

How  to  tell  them  from  each  other:  The  pine  needles 
are  arranged  in  clusters',  see  Fig.  1.  Each  species  has  a 
certain  characteristic  number  of  needles  to  the  cluster  and 
this  fact  generally  provides  the  simplest  and  most  direct 
way  of  distinguishing  the  different  pines. 

In  the  white  pine  there  are  five  needles  to  each  cluster, 
in  the  pitch  pine  three,  and  in  the  Scotch  pine  two.  The 
Austrian  pine  also  has  two  needles  to  the  cluster,  but  the 
difference  in  size  and  character  of  the  needles  will  dis- 
tinguish this  species  from  the  Scotch  pine. 

THE  WHITE  PINE   (Pinus  strobus) 

Distinguishing  characters :  The  tree  can  be  told  at  close 
range  by  the  number  of  needles  to  each  cluster,  Fig.  2.  There 
are  five  needles  to  each  cluster  of  the  white  pine.  They 
are  bluish  green,  slender,  and  about  four  inches  in  length. 

At  a  distance  the  tree  may  be  told  by  the  right  angles 
which  the  branches  form  with  the  main  trunk,  Fig.  3.  No 
other  pine  shows  this  character. 

Form  and  size:  A  tall  tree,  the  stateliest  of  the  ever- 
greens. 

Range :  Eastern  North  America. 

Soil  and  location:  Prefers  a  deep,  sandy  soil,  but 
will  grow  in  almost  any  soil. 

Enemies :  Sucking  insects  forming  white  downy  patches 
on  the  bark  and  twigs,  the  white  pine  weevil,  a  boring  insect, 
and  the  white  pine  blister  rust,  a  fungus,  are  among  its  prin- 
cipal enemies. 

Value  for  planting:    Aside  from  its  value  as  an  orna- 


THE  PINES 


FIG.  3.— The  White  Pine. 


6  STUDIES  OF  TREES 

mental  tree,  the  white  pine  is  an  excellent  tree  to  plant 
on  abandoned  farms  and  for  woodlands  and  windbreaks 
throughout  the  New  England  States,  New  York,  Pennsyl- 
vania, and  the  Lake  States. 

Commercial  value:  The  wood  is  easily  worked,  light, 
durable,  and  will  not  warp.  It  is  used  for  naval  con- 
struction, lumber,  shingles,  laths,  interior  finish,  wooden 
ware,  etc. 

Other  characters :  The  fruit  is  a  cone,  four  to  six  inches 
long. 

Comparisons:  The  tree  is  apt  to  be  confused  with  the 
Bhotan  pine  (Pinus  excelsa),  which  is  commonly  grown  as 
an  ornamental  tree.  The  Bhotan  pine,  however,  has  needles 
uch  longer  and  more  drooping  in  appearance. 

THE  PITCH  PINE  (Pirns  rigida) 

Distinguishing  characters :  Here  there  are  three  needles 
to  each  cluster,  Fig.  4.  They  are  dark,  yellowish-green 
needles  about  four  inches  long.  The  rough-looking  branches 
of  the  tree  may  be  seen  studded  with  cones  throughout  the 
year,  and  clusters  cf  leaves  may  be  seen  sprouting  directly 
from  the  trunk  of  the  tree;  see  Fig.  5.  The  last  two  are 
very  characteristic  and  will  distinguish  the  tree  at  a  glance. 

Form  and  size:  It  is  a  low  tree  of  uncertain  habit 
and  extremely  rough  looking  at  every  stage  of  its  life. 
It  is  constantly  full  of  dead  branches  and  old  cones  which 
persist  on  the  tree  throughout  the  year. 

Range:    Eastern  United . States. 

Soil  and  location:  Grows  in  the  poorest  and  sandiest 
soils  where  few  other  trees  will  grow.  In  New  Jersey 
and  on  Long  Island  where  it  is  native,  it  proves  so  hardy 


THE  PINES  7 

and  persistent  that  it  often  forms  pure  stands  excluding 
other  trees. 


FIG.  4.— Twig  of  the  Pitch  Pine. 

Enemies:    None  of  importance. 

Value  for  planting:    Well  adapted    for    the  sea  coast 


8 


STUDIES  OF  TREES 


and  other  exposed  places.     It  is  of  extremely  uncertain 
habit  and  is  subject  to   the  loss  of  the  lower  limbs.     It 


FIG.  5. — The  Pitch  Pine. 

frequently  presents   a   certain  picturesqueness   of   outline, 
but  it  could  not  be  used  as  a  specimen  tree  on  the  lawn. 

Commercial  value:     The  wood  is  coarse  grained  and  is 
used  for  rough  lumber,  fuel,  and  charcoal. 


THE  PINES  9 

Other  characters:  The  fruit  is  a  cone  one  to  three 
inches  long,  persistent  on  the  tree  for  several  years. 

THE  SCOTCH  PINE  (Pinus  sylvestris) 

Distinguishing  characters:  There  are  two  needles  to 
each  cluster,  and  these  are  short  compared  with  those  of  the 
white  pine,  and  slightly  twisted',  see  Fig.  6.  The  bark, 
especially  along  the  upper  portion  of  the  trunk,  is  reddish 
in  color. 

Form  and  size:  A  medium-sized  tree  with  a  short 
crown. 

Range:    Europe,  Asia,  and  eastern  United  States. 

Soil  and  location:  Will  do  best  on  a  deep,  rich,  sandy 
soil,  but  will  also  grow  on  a  dry,  porous  soil. 

Enemies:  In  Europe  the  Scotch  pine  has  several 
insect  enemies,  but  in  America  it  appears  to  be  free  from 
injury. 

Value  for  planting:  Suitable  for  windbreaks  and  wood- 
land planting.  Many  excellent  specimens  may  also  be 
found  in  our  parks. 

Commercial  value:  In  the  United  States,  the  wood 
is  chiefly  used  for  fuel,  though  slightly  used  for  barrels, 
boxes,  and  carpentry.  In  Europe,  the  Scotch  pine  is  an 
important  timber  tree. 

Comparisons:  The  Scotch  pine  is  apt  to  be  confused 
with  the  Austrian  pine  (Pinus  austriaca),  because  they 
both  have  two  needles  to  each  cluster.  The  needles  of 
the  Austrian  pine,  however,  are  much  longer,  coarser, 
straighter,  and  darker  than  those  of  the  Scotch  pine; 
Fig.  1.  The  form  of  the  Austrian  pine,  too,  is  more  sym- 
metrical and  compact. 


10 


STUDIES  OF  TREES 


. 


FIG.  6. — Twig  of  the  Scotch  Pine. 


THE    SPRUCE   AND   HEMLOCK  11 

The  red  pine  (Pinus  resinosa)  is  another  tree  that  has 
two  needles  to  each  cluster,  but  these  are  much  longer 
than  those  of  the  Scotch  pine  (five  to  six  inches)  and  are 
straighter.  The  bark,  which  is  reddish  in  color,  also  dif- 
ferentiates the  red  pine  from  the  Austrian  pine.  The 
position  of  the  cones  on  the  red  pine,  which  point  outward 
and  downward  at  maturity,  will  also  help  to  distinguish 
this  tree  from  the  Scotch  and  the  Austrian  varieties. 

GROUP  II.     THE  SPRUCE  AND  HEMLOCK 

How  to  tell  them  from  other  trees:  The  spruce  and 
hemlock  belong  to  the  evergreen  class  and  may  be  told 
from  the  other  trees  by  their  leaves.  The  characteristic 
leaves  of  the  spruce  are  shown  in  Fig.  9;  those  of  the 
hemlock  in  Fig.  10.  These  are  much  shorter  than  the 
needles  of  the  pines  but  are  longer  than  the  leaflets  of  the 
red  cedar  or  arbor  vitse.  They  are  neither  arranged  in 
clusters  like  those  of  the  larch,  nor  in  feathery  layers  like 
those  of  the  cypress.  They  adhere  to  the  tree  throughout 
the  year,  while  the  leaves  of  the  larch  and  cypress  shed  in 
the  fall. 

The  spruces  are  pyramidal-shaped  trees,  with  tall  and 
tapering  trunks,  thickly  covered  with  branches,  forming 
a  compact  crown.  They  are  widely  distributed  through- 
out the  cold  and  temperate  regions  of  the  northern  hemi- 
sphere, where  they  often  form  thick  forests  over  extended 
areas. 

There  are  eighteen  recognized  species  of  spruce.  The 
Norway  spruce  has  been  chosen  as  a  type  for  this  group 
because  it  is  so  commonly  planted  in  the  northeastern 
part  of  the  United  States. 

The  hemlock  is  represented  by  seven  species,  confined 


12 


STUDIES  OF  TREES 


FIG,  7. — The  Norway  Spruce. 


THE   SPRUCE   AND   HEMLOCK  13 

to    temperate    North  America,   Japan,   and    Central    and 
Western  China. 

How  to  tell  them  from  each  other:  The  needles  and 
branches  of  the  spruce  are  coarse;  those  of  the  hemlock 
are  flat  and  graceful.  The  individual  leaflets  of  the  spruce, 
Fig.  9,  are  four-sided  and  green  or  blue  on  the  under  side, 
while  those  of  the  hemlock,  Fig.  10,  are  flat  and  are  marked 
by  two  white  lines  on  the  under  side. 

THE  NORWAY  SPRUCE  (Picea  excelsa) 

Distinguishing  characters:  The  characteristic  appear- 
ance of  the  full-grown  tree  is  due  to  the  drooping  branch- 
lets  carried  on  main  branches  which  bend  upward  (Fig.  7). 

Leaf:  The  leaves  are  dark  green  in  color  and  are 
arranged  spirally,  thus  making  the  twigs  coarser  to  the 
touch  than  the  twigs  of  the  hemlock  or  fir.  In  cross-sec- 
tion, the  individual  leaflet  is  quadrilateral,  while  that  of 
the  pine  is  triangular. 

Form  and  size :  A  large  tree  with  a  straight,  undivided 
trunk  and  a  wrell-shaped,  conical  crown  (Fig.  7). 

Range:  Northern  Europe,  Asia,  northern  North 
America. 

Soil  and  location:     Grows  in  cool,  moist  situations. 

Enemies :  The  foliage  of  .  the  spruce  is  sometimes 
affected  by  red  spider,  but  is  apt  to  be  more  seriously  injured 
by  drought,  wind,  and  late  frosts. 

Value  for  planting:  Commonly  planted  as  an  orna- 
mental tree  and  for  hedges.  It  does  well  for  this  purpose 
in  a  cool  northern  climate,  but  in  the  vicinity  of  New  York 
City  and  further  south  it  does  not  do  as  well,  losing  its 
lower  branches  at  an  early  age,  and  becoming  generally 
scraggly  in  appearance. 


14 


STUDIES  OF  TREES 


FIG.  8.— A  Group  of  Hemlock. 


THE   SPRUCE   AND   HEMLOCK  15 

Commercial  value:  The  wood  is  light  and  soft  and  is 
used  for  construction  timber,  paper  pulp,  and  fuel. 

Other  characters:  The  fruit  is  a  large  slender  cone, 
four  to  seven  inches  long. 

Comparisons:  The  white  spruce  (Picea  canadensis) 
may  be  told  from  the  Norway  spruce  by  the  whitish  color 
on  the  under  side  of  its  leaves  and  the  unpleasant,  pungent 
odor  emitted  from  the  needles  when  bruised.  The  cones 
of  the  white  spruce,  about  two  inches  long,  are  shorter 
than  these  of  the  Norway  spruce,  but  are  longer  than  those 
of  the  black  spruce. 

It  is  essentially  a  northern  tree  growing  in  all  sorts  of 
locations  along  the  streams  and  on  rocky  mountain  slopes 
as  far  north  as  the  Arctic  Sea  and  Alaska.  It  often  appears 
as  an  ornamental  tree  as  far  south  as  New  York  and  Penn- 
sj  Ivania. 

The  black  spruce  (Picea  mariana)  may  be  told  from  the 
other  spruces  by  its  small  cone,  which  is  usually  only  about 
one  inch  in  length.  In  New  England  it  seldom  grows  to 
as  large  a  size  as  the  other  spruce  trees. 

It  covers  large  areas  in  various  parts  of  northern  North 
America  and  grows  to  its  largest  size  in  Manitoba.  The 
black  spruce  has  little  value  as  an  ornamental  tree. 

The  Colorado  blue  spruce  (Picea  parryana  or  Picea 
pungens)  which  is  commonly  used  as  an  ornamental  tree 
en  lawns  and  in  parks,  can  be  told  from  the  other  spruces 
by  its  pale-blue  or  sage-green  color  and  its  sharp-pointed, 
coarse-feeling  twigs.  Its  small  size  and  sharp-pointed 
conical  form  are  also  characteristic. 

It  grows  to  a  large  size  in  Colorado  and  the  Middle  West. 
In  the  Eastern  States  and  in  northern  Europe  where  it  is 
planted  as  an  ornamental  tree,  it  is  usually  much  smaller. 


16 


STUDIES  OF  TREES 


FIG.  9. — Twis  of  the  Norway  Spruce. 


THE    SPRUCE    AND   HEMLOCK  17 


HEMLOCK  (Tsuga  canadensis) 

Distinguishing  characters:  Its  leaves  are  arranged  in 
flat  layers,  giving  a  flat,  horizontal  and  graceful  appear- 
ance to  the  whole  branch  (Fig.  8).  The  individual  leaflets 
are  dark  green  above,  lighter  colored  below,  and  are  marked 
by  two  white  lines  on  the  under  side  (Fig.  10). 

The  leaflets  are  arranged  on  little  stalks,  a  character- 
istic that  does  not  appear  in  the  other  evergreen  trees. 

Form  and  size :  A  large  tree  with  a  broad-based  pyram- 
idal head,  and  a  trunk  conspicuously  tapering  toward 
the  apex.  The  branches  extend  almost  to  the  ground. 

Range:  The  hemlock  is  a  northern  tree,  growing  in 
Canada  and  the  United  States. 

Soil  and  location:  Grows  on  all  sorts  of  soils,  in  the 
deepest  woods  as  well  as  on  high  mountain  slopes. 

Enemies:    None  of  importance. 

Value  for  planting:  The  hemlock  makes  an  excellent 
hedge  because  it  retains  its  lowest  branches  and  will  stand 
shearing.  In  this  respect  it  is  preferable  to  the  spruce. 
It  makes  a  fair  tree  for  the  lawn  and  is  especially  desirable 
for  underplanting  in  woodlands,  where  the  shade  from 
the  surrounding  trees  is  heavy.  In  this  respect  it  is  like 
the  beech. 

Commercial  value:  The  wood  is  soft,  brittle,  and 
coarse-grained,  and  is  therefore  used  mainly  for  coarse 
lumber.  Its  bark  is  so  rich  in  tannin  that  it  forms  one  of 
the  chief  commercial  products  of  the  tree. 

Other  characters:  The  fruit  is  a  small  cone  about  f 
cf  an  inch  long,  which  generally  hangs  on  the  tree  all  winter. 


18 


STUDIES  OF  TREES 


FIG.  10.— Twig  of  the  Hemlock. 


THE  RED  CEDAR  AND  ARBOR-VITAE  19 


GROUP  III.     THE  RED  CEDAR  AND  ARBOR-VITAE 

How  to  tell  them  from  other  trees:  The  red  cedar 
(juniper)  and  arbor-vitae  may  be  told  from  other  trees  by 
their  leaves,  which  remain  on  the  tree  and  keep  green 
throughout  the  entire  year.  These  leaves  differ  from  those 
of  the  other  evergreens  in  being  much  shorter  and  of  a 
distinctive  shape  as  shown  in  Figs.  12  and  13.  The  trees 
themselves  are  much  smaller  than  the  other  evergreens 
enumerated  in  this  book.  Altogether,  there  are  thirty- 
five  species  of  juniper  recognized  and  four  of  arbor  vitse. 
The  junipers  are  widely  distributed  over  the  northern 
hemisphere,  from  the  Arctic  region  down  to  Mexico  in  the 
New  World,  and  in  northern  Africa,  China,  and  Japan 
in  the  Old  World.  The  arbor-vitse  is  found  in  northeastern 
and  northwestern  America,  China,  and  Japan.  -The  species 
mentioned  here  are  those  commonly  found  in  America. 

How  to  tell  them  from  each  other:  The  leaves  of  the 
arbor-vitae  are  flat  and  fan-like  as  in  Fig.  13;  the  leaves  of 
the  red  cedar  are  needle-shaped  or  scale-like  as  in  Fig.  12. 
The  foliage  of  the  arbor-vitse  is  of  a  lighter  color  than  that 
of  the  red  cedar,  which  is  sombre  green.  The  arbor-vita; 
will  generally  be  found  growing  in  moist  locations,  while 
the  red  cedar  will  grow  in  dry  places  as  well.  The  arbor- 
vitae  generally  retains  its  lower  branches  in  open  places, 
while  the  branches  of  the  red  cedar  start  at  some  distance 
from  the  ground. 

RED  CEDAR  (Juniperus  virginiana) 

Distinguishing  characters:  The  tree  can  best  be  told 
at  a  glance  by  its  general  form,  size  and  leaves.  It  is  a 
medium-sized  tree  with  a  symmetrical,  cone-like  form, 


20 


STUDIES  OF  TREES 


FIG.  11.— The  Red  Cedar. 


THE  RED  CEDAR  AND  ARBOR-VITAE 


21 


Fig.  11,  which,  however,  broadens  out  somewhat  when 
the  tree  grows  old.  Its  color  throughout  the  year  is  dull 
green  with  a  tinge  of  brownish  red,  and  its  bark  peels  in 
thin  strips. 


FIG.  12(a). 
Twig  of  Young  Cedar. 


FIG.  12(6). 
Twig  of  Cedar  (Older  Tree). 


Leaf:  In  young  trees  the  leaf  is  needle-shaped,  pointed, 
and  marked  by  a  white  line  on  its  under  side,  Fig.  12(a). 
In  older  trees  it  is  scale-like,  Fig.  12(6),  and  the  white  line 
on  its  under  side  is  indistinct. 


22  STUDIES  OF  TREES 

Range:  Widely  distributed  over  nearly  all  of  eastern 
and  central  North  America. 

Soil  and  location:  Grows  on  poor,  gravelly  soils  as 
well  as  in  rich  bottom  lands. 

Enemies:  The  "  cedar  apple"  commonly  found  on 
this  tree,  represents  a  stage  of  the  apple  r'st,  and  for  that 
reason  it  is  not  desirable  to  plant  such  trees  near  orchards. 
Its  wood  is  also  sometimes  attacked  by  small  boring  insects. 

Value  for  planting:  Its  characteristic  slender  form 
gives  the  red  cedar  an  important  place  as  an  ornamental 
tree,  but  its  chief  value  lies  in  its  commercial  use. 

Commercial  value:  The  wood  is  durable,  light,  smooth 
and  fragrant,  and  is  therefore  used  for  making  lead-pencils, 
cabinets,  boxes,  moth-proof  chests,  shingles,  posts,  and 
telegraph  poles. 

Other  characters :  The  fruit  is  small,  round  and  berry- 
like,  about  the  size  of  a  pea,  of  dark  blue  color,  and  carries 
from  one  to  four  bony  seeds. 

Other  common  names :  The  red  cedar  is  also  often  called 
juniper  and  red  juniper. 

Comparisons:  The  red  cedar  is  apt  to  be  confused 
with  the  low  juniper  (Juniperus  communis)  which  grows 
in  open  fields  all  over  the  world.  The  latter,  however, 
is  generally  of  a  low  form  with  a  flat  top.  Its  leaves  are 
pointed  and  prickly,  never  scale-like,  and  they  are  whitish 
above  and  green  below.  Its  bark  shreds  and  its  fruit  is 
a  small  round  berry  of  agreeable  aromatic  rdor. 

ARBOR-VITAE;    NORTHERN  WHITE  CEDAR  (Thuja  occi- 

dentalis} 

Distinguishing  characters :  The  branchlets  are  extremely 
flat  and  fan-like,  Fig.  13,  and  have  an  agreeable  aromatic 


THE  RED  CEDAR  AND  ARBOR-VITAE 


23 


odor  when  bruised.     The  tree  is  an  evergreen  with  a  narrow 
conical  form. 


FIG.  13.— Twig  of  the  Arbor-vitae. 

Leaf:  Each  leaf  consists  of  two  flat  leaflets  in  the 
center  surrounded  by  two  keel-shaped  leaflets  on  the  side. 

Form  and  size:  A  close,  conical  head  with  dense 
foliage  near  the  base.  Usually  a  small  tree,  but  in  some 


24  STUDIES  OF  TREES 

parts  of  the  northeastern  States  it  grows  to  medium  size 
with  a  diameter  of  two  feet. 

Range:     Northern  part  of  North  America. 

Soil  and  location:  Inhabits  low,  swampy  lands;  in 
the  State  of  Maine  often  forming  thick  forests. 

Enemies:    Very  seldom  affected  by  insects. 

Value  for  planting:  Is  hardy  in  New  England,  where 
it  is  especially  used  for  hedges.  It  is  also  frequently  used 
as  a  specimen  tree  on  the  lawn. 

Commercial  value:  The  wood  is  durable  for  posts, 
ties,  and  shingles.  The  bark  contains  considerable  tannin 
and  the  juices  from  the  tree  have  a  medicinal  value. 

Other  characters :    The  fruit  is  a  cone  about  J  inch  long, 

Other  common  names :  Arbor-vitae  is  sometimes  called 
white  cedar  and  cedar. 

Comparisons:  The  arbor-vitae  is  apt  to  be  confused 
with  the  true  white  cedar  (Chamcecyparis  Ihyoides)  but  the 
leaves  of  the  latter  are  sharp-pointed  and  not  flattened 
or  fan-shaped. 


CHAPTER  II 
HOW  TO  IDENTIFY  TREES—  (Continued} 

GROUP  IV.     THE  LARCH  AND  CYPRESS 

How  to  tell  them  from  other  trees:  In  summer  the 
larch  and  cypress  may  easily  be  told  from  other  trees 
by  their  leaves.  These  are  needle-shaped  and  arranged 
in  clusters  with  numerous  leaflets  to  each  cluster  in  the  case 
of  the  larch,  and  feathery  and  flat  in  the  case  of  the 
cypress.  In  winter,  when  their  leaves  have  dropped  off, 
the  trees  can  be  told  by  their  cones,  which  adhere  to  the 
branches. 

There  are  nine  recognized  species  of  larch  and  two  of 
bald  cypress.  The  larch  is  characteristically  a  northern 
tree,  growing  in  the  northern  and  mountainous  regions 
of  the  northern  hemisphere  from  the  Arctic  circle  to  Penn- 
sylvania in  the  New  World,  and  in  Central  Europe,  Asia, 
and  Japan  in  the  Old  World.  It  forms  large  forests  in 
the  Alps  of  Switzerland  and  France. 

The  European  larch  and  not  the  American  is  the  prin- 
cipal species  considered  here,  because  it  is  being  planted 
extensively  in  this  country  and  in  most  respects  is  prefer- 
able to  the  American  species. 

The  bald  cypress  is  a  southern  tree  of  ancient  origin, 
the  well-known  cypress  of  Montezuma  in  the  gardens  of 
Chepultepec  having  been  a  species  of  Taxodium.  The 
tree  is  now  confined  to  the  swamps  and  river  banks  of  the 

25 


26 


STUDIES  OF  TREES 


F 


South  Atlantic  and  Gulf  States,  where  it  often  forms 
extensive  forests  to  the  exclusion  of  all  other  trees.  In 
those  regions  along  the  river  swamps,  the  trees  are  often 
submerged  for  several  months  of  the  year. 

How  to  tell  them  from  each  other:  In  summer  the 
larch  may  be  told  from  the  cypress  by  its  leaves  (com- 
pare Figs.  14  and  16).  In  winter  the  two  can  be  dis- 
tinguished by  their  characteristic 
forms.  The  larch  is  a  broader  tree 
as  compared  with  the  cypress  and 
its  form  is  more  conical.  The  cy- 
press is  more  slender  and  it  is  taller. 
The  two  have  been  grouped  together 
in  this  study  because  they  are  both 
coniferous  trees  and,  unlike  the  other 
Conifers,  are  both  deciduous,  their 
leaves  falling  in  October. 

THE  EUROPEAN  LARCH  (Larix 
europaea) 


FIG.  14.— Twig  of  the 
Larch  in  Summer. 


Distinguishing  characters :  Its 
leaves,  which  are  needle-shaped  and 
about  an  inch  long,  are  borne  in 
clusters  close  to  the  twig,  Fig.  14. 
There  are  many  leaflets  to  each  cluster.  This  character- 
istic together  with  the  spire-like  form  of  the  crown  will 
distinguish  the  tree  at  a  glance. 

Leaf:  The  leaves  are  of  a  light-green  color  but  become 
darker  in  the  spring  and  in  October  turn  yellow  and  drop 
off.  The  cypress,  which  is  described  below,  is  another 
cone-bearing  tree  which  sheds  its  leaves  in  winter. 


THE  LARCH  AND  CYPRESS 


27 


Form  and  size : 
A  m  e  d  i  u  m-sized 
tree  with  a  conical 
head  and  a  straight 
and  tapering  trunk. 
(See  Fig.  90.) 

Range:  Central 
Europe  and  eastern 
and  central  United 
States. 

Soil  and  loca- 
tion: Requires  a 
deep,  fresh,  well- 
drained  soil  and 
needs  plenty  of 
light.  It  flourishes 
in  places  where  our 
native  species  would  die. 
very  rapidly. 

Enemies :  The  larch  is  sub- 
ject to  the  attacks  of  a  sawfly, 
which  has  killed  many  trees  of 
the  American  species.  A  fungus 
(Trametes  pini)  which  causes  the 
tree  to  break  down  with  ease  is 
another  of  its  enemies. 

Value  for  planting:  A  well- 
formed  tree  for  the  lawn.  It  is 
also  useful  for  group  planting  in 
the  forest. 

Commercial  value:  Because 
its  wood  is  strong  and  durable 
the  larch  is  valuable  for  poles, 
posts,  railroad  ties,  and  in  ship  builamg. 


FIG.  15.— Twig 

of  the  Larch 

in  Winter. 


28 


STUDIES  OF  TREES 


FIG.  16. — Twig  of  the  Cypress. 


THE  LARCH   AND  CYPRESS 


29 


Other  characters:  The  fruit  is  a  small  cone  about 
1  alf  an  inch  lonj,  adhering  to  the  tree  throughout  the 
winter. 

Comparisons :  The  tree 
is  apt  to  be  confused  with 
the  American  larch,  also 
known  as  tamarack  and 
hackmatack,  but  differs 
from  it  in  having  longer 
leaves,  cones  twice  as 
large  and  more  abundant 
and  branches  which  are 
more  pendulous. 

The  larch  differs  from 
the  bald  cypress  in  the 
broader  form  of  its  crown 
and  the  cluster-like  ar- 
rangement of  its  leaves. 
The  leaves  of  the  bald 
cypress  are  flat  and  feath- 
ery. The  larch  and  bald 
cypress  have  the  common 
characteristics  of  both 
shedding  their  leaves  in 
winter  and  preferring  to 
grow  in  moist  or  swampy 
soils.  The  larch,  especi- 
ally the  native  species, 

forms    the    well-known  FIG.  17. — The  Bald  Cypress, 

tamarack  swamps  of  the 

north.     The  bald  cypress  grows  in  a  similar  way  in  groups 
in  the  southern  swamps. 


30 


STUDIES  OF  TKEES 


BALD  CYPRESS  (Taxodium  distichum) 

Distinguishing  characters:  The  feathery  character  of 
the  leaves,  Fig.  16,  and  the  spire-like  form  of  the  tree, 
Fig.  17,  which  is  taller  and  more  slender  than  the  larch, 
will  distinguish  this  species  from  others. 


FIG.  18.— Cypress  "Knees." 

Leaf:  The  leaves  drop  off  in  October,  though  the  tree 
is  of  the  cone-bearing  kind.  In  this  respect  it  is  like  the 
larch. 

Form  and  size :    Tall  and  pyramidal. 

Range:  The  cypress  is  a  southern  tree,  but  is  found 
under  cultivation  in  parks  and  on  lawns  in  northern  United 
States. 

Soil  and  location:  Grows  naturally  in  swamps,  but 
will  also  do  well  in  ordinary  well-drained,  good  soil.  In 


THE  LARCH  AND   CYPRESS  31 

its  natural  habitat  it  sends  out  special  roots  above  water. 
These  are  known  as  "  cypress  knees  "  (Fig.  18)  and  serve  to 
provide  air  to  the  submerged  roots  of  the  tree. 

Enemies:     None  of  importance. 

Value  for  planting:  An  excellent  tree  for  park  and 
lawn  planting. 

Commercial  value:  The  wood  is  light,  soft,  and  easily 
worked.  It  is  used  for  general  construction,  interior  finish, 
railroad  ties,  posts  and  cooperage. 

Other  characters:  The  bark  is  thin  and  scaly.  The 
fruit  is  a  cone  about  an  inch  in  diameter.  The  general 
color  of  the  tree  is  a  dull,  deep  green  which,  however,  turns 
orange  brown  in  the  fall. 

Comparisons:  The  cypress  and  the  larch  are  apt  to  be 
confused,  especially  in  the  winter,  when  the  leaves  of  both 
have  dropped.  The  cypress  is  more  slender  and  is  taller 
in  form.  The  leaflets  of  each  are  very  different,  as  will 
be  seen  from  the  accompanying  illustrations. 


GROUP  V.     THE  HORSECHESTNUT,  ASH  AND  MMLE 

How  to  tell  them  from  other  trees:  The  horsechestnut, 
ash,  and  maple  have  their  branches  and  buds  arranged 
on  their  stems  opposite  each  other  as  shown  in  Figs.  20, 
22  and  24.  In  other  trees,  this  arrangement  is  alternate, 
as  shown  in  Fig.  19. 

How  to  tell  these  three  from  each  other.  If  the  bud 
is  large — an  inch  to  an  inch  and  a  half  long — dark  brown, 
and  sticky,  it  is  a  horsechestnut. 

If  the  bud  is  not  sticky,  much  smaller,  and  rusty  brown 
to  black  in  color,  and  the  ultimate  twigs,  of  an  olive  green 
color,  are  flattened  at  points  below  the  buds,  it  is  an  ash. 


32 


STUDIES  OF  TREES 


FIG.  19. — Alternate  Branching  (Beech.) 


If  it  is  not  a  horse- 
chestnut  nor  an  ash 
and  its  small  buds  have 
many  scales  covering 
them,  the  specimen 
with  branches  and  buds 
opposite  must  then  be 
a  maple.  Each  of  the 
maples  has  one  charac- 
ter which  distinguishes 
it  from  all  the  other 
maples.  For  the  sugar 
maple,  this  distinguish- 
ing character  is  the 
sharp  point  of  the  bud. 
For  the  silver  maple 
it  is  the  bend  in  the  ter- 
minal twig.  For  the  red 
maple  it  is  the  smooth 
gray-colored  bark.  For 
the  Norway  maple  it  is 
the  reddish  brown  color 
of  the  full,  round  bud, 
and  for  the  box  elder 
it  is  the  greenish  color 
of  its  terminal  twig. 

The  form  of  the 
tree  and  the  leaves  are 
also  characteristic  in 
each  of  the  maples,  but 
for  the  beginner  who 
does  not  wish  to  be 
burdened  with  too 


THE   HORSECHESTNUT,  ASH   AND  MAPLE         33 


many  of  these  facts  at  one  time, 
those  just  enumerated  will  be 
found  most  certain  and  most 
easily  followed. 

THE   HORSECHESTNUT 

(JEsculus  hippocastanum) 

Distinguishing  characters : 
The  sticky  nature  of  the  ter- 
minal bud  and  its  large  size 
(about  an  inch  long).  The  bud 
is  dark  brown  in  color.  See  Fig. 
20. 

Leaf :  Five  to  seven  leaflets, 
usually  seven.  Fig.  21. 

Form  and  size:  Medium- 
sized  tree,  pyramidal  head  and 
coarse  twigs. 

Range:  Europe  and  eastern 
United  States. 

Soil  and  location:    Prefers  a 
deep,  rich  soil. 

Enemies:  The  leaves  are 
the  favorite  food  of  caterpillars 
and  are  subject  to  a  blight  which 
turns  them  brown  prematurely. 
The  trunk  is  often  attacked  by 
a  disease  which  causes  the  flow 
of  a  slimy  substance. 

Value  for  planting:    On  account  of  its  showy  flowers, 
the  horsechestnut  is  a  favorite  for  the  park  and  lawn. 


FIG.  20. — Opposite  Branch- 
ing (Horsechestnut.) 


34 


STUDIES  OF  TREES 


Commercial  value:  The  wood  is  not  durable  and  is 
not  used  commercially. 

Other  characters:  The  flowers  appear  in  large  white 
clusters  in  May  and  June.  The  fruit  is  large,  round,  and 
prickly. 


FIG.  21. — Leaf  of  the  Horsechestnut. 


Comparisons:  The  red  horsechestnut  differs  from  this 
tree  in  having  red  flowers.  The  buckeye  is  similar  to  the 
horsechestnut,  but  its  bud  is  not  sticky  and  is  of  a  lighter 
gray  color,  while  the  leaf  generally  has  only  five  leaflets. 


THE   HORSECHESTNUT,  ASH   AND   MAPLE          35 


THE  WHITE  ASH  (Fraxinus  americana) 

Distinguishing  characters :  The  terminal  twigs  of  glossy 
olive  green  color  are  flattened  below  the  bud.  Fig.  22. 
The  bud  is  rusty-brown. 

Leaf:  Five  to  nine  leaflets. 
Fig.  23. 

Form  and  size:  A  large  tree 
with  a  straight  trunk. 

Range :  Eastern  North  Amer- 
ica. 

Soil  and  location:  Rich, 
moist  soil. 

Enemies:  In  cities  it  is  very 
often  attacked  by  sucking  in- 
sects. 

Value  for  planting :  The 
white  ash  grows  rapidly.  On 
account  of  its  insect  enemies  in 
cities,  it  should  be  used  more  for 
forest  planting  and  only  oc- 
casionally for  ornament. 

Commercial  value:  It  has  a 
heavy,  tough,  and  strong  wood, 
which  is  valuable  in  the  manu- 
facture of  cooperage  stock,  agri- 
cultural implements,  and  carriages, 
to  the  black  ash. 

Other  characters:  The  bark  is  gray.  The  flowers 
appear  in  May. 

Comparisons :  The  white  ash  is  apt  to  be  confused  with 
the  black  ash  (Fraxinus  nigra),  but  differs  from  the  latter 


FIG.  22.— Twig  of  White  Ash. 


It  is  superior  in  value 


36 


STUDIES  OF  TREES 


in  having  a  lighter-colored  bud.     The  bud  of  the  black  ash 
is  black.     The  bark  of  the  white  ash  is  darker  in  color 


FIG.  23.— Leaf  of  White  Ash. 


and  the  terminal  twigs  are  more  flattened  than  those  of 
the  black  ash. 


THE   HORSECHESTNUT,  ASH  AND  MAPLE         37 

SUGAR  MAPLE  (Acer  saccharum) 

Distinguishing  characters:    The  bud  is  sharp-pointed, 

scaly,  and  reddish  brown.     Fig.  24. 

Leaf:  Has  sharp  points 
and  round  sinus.  Fig.  25. 

Form  and  size:  The 
crown  is  oval  when  the  tree 
is  young  and  round  in  old 
age.  Fig.  26. 

Range:  Eastern  United 
States. 

Soil  and  location :  Moist 
and  deep  soil,  and  cool,  shady 
positions. 

Enemies :  Subject  to 
drouth,  especially  in  cities. 
Is  attacked  by  the  sugar 
maple  borer  and  the  maple 
phenacoccus,  a  sucking  insect. 

Value  for  planting:  Its 
rich  and  yellow  color  in  the 
fall,  and  the  fine  spread  of 
its  crown  make  it  a  desir- 
able tree  for  the  lawn,  es- 
pecially in  the  country.  FlG  24._^ig  of  the  Sugar 

Commercial   value:     Its  Maple, 

wood  is   hard  and  takes  a 

good  polish;  used  for  interior  finish  and   furniture.     The 
tree  is  also  the  source  of  maple  sugar.     Fig.  27. 

Other  characters:  The  bark  is  smooth  in  young  trees 
and  in  old  trees  it  shags  in  large  plates.  The  flowers 
appear  in  the  early  part  of  April. 


38 


STUDIES   OF  TREES 


Other    common    names:     The    sugar    maple    is    some- 
times called  rock  maple  or  hard  maple. 

SILVER  MAPLE  (Acer  saccharinum) 
Distinguishing    characters:     The  terminal  twigs  curve 
ipwards   (Fig.  28\  the  bark  is  scaly,  and  the  leaves  are 
very  deeply  cleft  and  are  silvery  on  the  under  side. 


FIG.  25. — Leaf  of  Sugar  Maple. 

Leaf:    Deeply  cleft  and  silvery  under  side.     Fig.  29. 

Form  and  size:  A  large  tree  with  the  main  branches 
separating  from  the  trunk  a  few  feet  from  the  ground. 
The  terminal  twigs  are  long,  slender,  and  drooping. 


THE  HORSECHESTNUT,   ASH  AND   MAPLE 


39 


Range:     Eastern  United  States. 
Soil  and  location:    Moist  places. 

Enemies:    The  leopard  moth,  a  wood-boring  insect,  and 
the  cottony-maple  scale,  a  sucking  insect. 


FIG.  26.— The  Sugar  Maple. 


Value  for  planting:  Grows  too  rapidly  and  is  too  short- 
lived to  be  durable. 

Commercial  value:  Its  wood  is  soft,  weak,  and  little 
used. 

Other  characters:  The  bark  is  light  gray,  smooth  at 
first  and  scaly  later  on.  The  scales  are  free  at  each  end 


40 


STUDIES  OF  TREES 


and  attached  in  the  center.     The  flowers  appear  before  the 
leaves  in  the  latter  part  of  March  or  early  April. 


FIG.  27. — Tapping  the  Sugar  Maple. 

Other  common  names:    The  silver  maple  is  sometimes 
known  as  soft  maple  or  white  maple. 


THE   HORSECHESTNUT,  ASH   AND  MAPLE         41 

RED  MAPLE  (Acer  rubrum) 

Distinguishing  characters:  The  bark  is  smooth  and 
light  gray,  like  that  of  the  beech,  on  the  upper  branches 
in  older  trees,  and  in  young  trees  over  the  whole  trunk. 

Fig.  30.  The  buds  are  in  clusters, 
and  the  terminal  twigs,  Fig.  31,  are 
quite  red. 


FIG.  29.— Leaf  of  the  Silver  Maple. 

Leaf:  Whitish  underneath  with 
three-pointed  lobes.     Fig.  32. 

FIG.  28.— Terminal  Twig  Form    *&&    siz^:      A     medhim- 

of  Silver  Maple.  sized    tree    with    a   narrow,   round 

head. 

Range:     Eastern  North  America. 
Soil  and  location:     Prefers  moist  places. 
Enemies:     Leaf  blotches    (Rhytisma   acerinum)    which, 
however,  are  not  very  injurious. 

Value  for  planting:    Suitable  as  a  shade  tree  for  subur- 


42 


STUDIES  OF  TREES 


ban  streets.     Its  rich  red  leaves  in  the  fall  make  it  attractive 
for  the  lawn. 


FIG.  30.— Bark  of  the  Red  Maple. 

Commercial  value:  Its  wood  is  heavy,  close-grained, 
and  takes  a  good  polish.  Used  for  furniture  and  fuel. 

Other  characters:  The  bud  is  small,  round,  and  red. 
The  flowers  appear  before  the  leaves  are  out  in  the  early 
part  of  April. 


THE   HORSECHESTNUT,  ASH  AND   MAPLE         43 

Other  common  names:  The 
red  maple  is  sometimes  known 
as  swamp  maple. 

Comparisons:  The  red  maple 
is  apt  to  be  confused  with  the 


FIG.  32. — Leaf  of  the  Red 


FIG.  31.— Twig 

of  the  Red 

Maple. 


FIG.  33. 
Twig  of 
Norway 
Maple. 


silver  maple,  but  the  latter  can 
be  distinguished  by  its  turned- 
up  twigs  and  scaly  bark  over 
the  whole  trunk  of  the  tree, 

which  presents  a  sharp  contrast  to  the  straight  twig  and 
smooth  bark  of  the  red  maple.  The  latter  has  a  bark 
similar  to  the  beech,  but  its  branches  are  opposite,  while 
those  of  the  beech  are  alternate. 


44 


STUDIES  OF  TREES 


NORWAY  MAPLE  (Acer  platanoides) 

Distinguishing  characters:    The  bud,  Fig.  33,  is  oval 
and  reddish-brown  in  color;    when  broken  off,     a  milky 

juice  exudes.  The  bark  is  close. 
Fig.  34. 

Leaf:  Like  the  leaf  of  the 
sugar  maple  but  thicker  in  text- 
ure and  darker  in  color.  Fig. 
35. 

Form  and  size:  A  tall  tree 
with  a  broad,  round  head. 

Range  :  Europe  and  the 
United  States. 

Soil  and  location:  Will  grow 
in  poor  soil. 

Enemies:    Very  few. 

Value  for  planting:  One  of 
the  best  shade  trees. 

Commercial  value:    None. 

Other  characters:  The  bark 
is  close  like  that  of  the  mocker- 
nut  hickory. 

Comparisons:  The  Norway 
maple  is  apt  to  be  confused 
with  the  sycamore  maple  (Acer 

pseudoplatanus) ,  but  differs  from  the  latter  in  having  a 
reddish  bud  instead  of  a  green  bud,  and  a  close  bark  in- 
stead of  a  scaly  bark. 


FIG.  34.— Bark  of  Norway 
Maple. 


THE   HORSECHESTNUT,  ASH  AND  MAPLE         45 

BOX  ELDER  (Acer  negundo) 

Distinguishing    characters:    The    terminal    twigs    are 
green,  and  the  buds  are  round  and  small.     Fig.  36. 
Leaf:     Has  three  to  seven  leaflets. 


FIG.  35. — Leaf  of  Norway  Maple. 

Form  and  size:  A  medium-sized  tree  with  a  short 
trunk  and  wide-spreading  top. 

Range:  Eastern  United  States  to  the  Rocky  Moun- 
tains. 

Soil  and  location:  Grows  rapidly  in  deep,  moist  soil 
and  river  valleys,  but  accommodates  itself  to  the  dry  and 
poor  soil  conditions  of  the  city. 


46  STUDIES  OF  TREES 

Enemies :    Few. 

Value  for  planting:  Used  as  a  shade  tree  in 
the  Middle  West,  but  the  tree  is  so  ill  formed 
and  so  short-lived  that  it  is  not  to  be  recom- 
mended. 

Commercial  value:  None.  The  wood  is 
soft. 

Other  characters:  The  bark  of  the  trunk  is 
smooth  and  yellowish-green  in  young  trees  and 
grayish  brown  in  older  specimens.  The  flowers 
appear  in  the  early  part  of  April.  The  fruit 
takes  the  form  of  yellowish-green  keys  which 
hang  on  the  tree  till  late  fall. 

Other  common  names :  The  box  elder  is  also 
commonly  known  as  the  ash-lccf  maple, 


GROUP  VI.    TREES  TOLD  BY  THEIR  FORM: 
ELM,  POPLAR,  GINGKO  AND  WILLOW 

How  to   tell  them  from  other  trees:     The 

trees  described  in  this   group  are  so  distinctive 
FIG.  36.      in  their    general  form  that    they    may,  for  the 
purpose  of  study,  be  grouped  together,  and  dis- 
Elder         tinguished  from  all  other  trees  by  this  charac- 
teristic. 

How  to  tell  them  from  each  other:  The  American 
elm  is  vase-like  in  shape;  the  Lombardy  poplar  is  narrow 
and  spire-like;  the  gingko,  or  maidenhair  tree,  is  odd  in  its 
mode  of  branching;  and  the  weeping  willow  is  extremely 
pendulous. 


TREES   TOLD   BY  THEIR  FORM 


47 


AMERICAN  ELM  (Ulmus  americana) 

Distinguishing   characters:     The   tree   can   be   told   at 
a  glance  by  its  general  branching  habit.     The  limbs  arch 


FIG.  37.— American  Elm. 

out  into  a  wide-spreading  fan  or  vase-like  crown  which 
loses  itself  in  numerous  fine  drooping  branchlets.  See 
Fig.  37. 


48 


STUDIES   OF  TREES 


Leaf:     The  leaves  are  simple,   alternate,   and  from  2 
to  5  inches  long. 


FIG,  38.— English  Elm  in  Winter. 


Form  and  size : 

a    short    distance 
tc  gether   with   the 


It  is  a  tall  tree  with  a  trunk  that  divides 
above  ground.  Its  general  contour, 
numerous  branches  that  interlace  its 


TREES  TOLD  BY  THEIR  FORM 


49 


massive  crown,  give  the 
elm  an  interesting  and 
stately  appearance  which 
is  unequaled  by  any  other 
tree. 

Range:  Eastern  North 
America. 

Soil  and  location :  The 
elm  prefers  a  deep,  rich 
and  moist  soil,  but  will 
adapt  itself  even  to  the 
poor  soil  of  the  city  street. 

Enemies:  The  leopard 
moth}  a  wood-boring  in- 
sect, and  the  elm  leaf 
beetle,  a  leaf-eating  insect, 
are  the  two  most  impor- 
tant enemies  of  the  tree. 
Their  ravages  are  very 
extensive. 

Value  for  planting : 
The  tree  has  a  character 
of  its  own  which  cannot 
be  duplicated  for  avenue 
or  lawn  planting. 

Commercial  value  : 
The  wood  is  strong  and 
tough  and  therefore  has  a 
special  value  for  cooper- 
age, agricultural  imple- 
ments, carriages,  and  ship- 
building. 

Other  characters:  The 


FIG.  39. — Lombardy  Poplar. 


STUDIES  OF  TREES 


buds  are  small,  brown,  and  smooth,  while  those  of  the 
European  elms  are  covered  with  down.  The  small  side 
twigs  come  out  at  almost  right  angles  to  the  larger  terminal 
twigs,  which  is  not  the  case  in  other  species  of  elm. 

Other    common 
names:     White  elm. 

Comparisons :  The 
English  elm  (Ulmus  cam- 
pestris)  is  also  a  tall, 
dignified  tree  commonly 
seen  under  cultivation 
in  America,  but  may  be 
told  from  the  American 
species  by  the  difference 
in  their  general  contour. 
The  branches  of  the 
English  species  spread 
out  but  do  not  arch  like 
those  of  the  American 
elm,  and  the  bark  of  the 
English  elm  is  darker 
and  coarser,  Fig.  38. 
Little  tufts  of  dead  twigs 
along  the  main  branches 
and  trunk  of  the  tree 
are  characteristic  of  the 
English  elm  and  will 
frequently  help  to  distinguish  it  from  the  American  elm. 

The  Camperdown  elm  may  be  recognized  readily  by  its 
dwarf  size  and  its  low  drooping  umbrella-shaped  crown. 


FIG.  40. — Leaf  of  Carolina  Poplar. 


TREES  TOLD  BY   THEIR  FORM  51 


LOMBARDY    OR    ITALIAN    POPLAR    (Populus    nigra,    var. 

italicd) 

Distinguishing  characters:  Its  tall,  slender,  spire- 
like  form  and  rigidly  erect  branches,  which  commence 
low  on  the  trunk,  make  this  tree  very  distinct  at  all  seasons 
of  the  year.  See  Fig.  39. 

Leaf:  Triangular  in  shape,  similar  to  that  of  the 
Carolina  poplar  but  smaller,  see  Fig.  40. 

Range:     Asia,  Europe,  and  North  America. 

Soil  and  location:  The  poplar  is  easily  grown  in  poor 
soil,  in  any  location,  and  is  very  hardy. 

Value  for  planting:  The  tree  has  a  distinctive  form 
which  makes  it  valuable  for  special  landscape  effects.  It 
is  also  used  for  shelter  belts  and  screening.  Like  all  pop- 
lars it  is  short  lived  and  will  stand  pruning  well. 

Commercial  value:    None. 

Comparisons:  The  Carolina  poplar,  or  Cottonwood 
(Populus  deltoides)  can  be  told  from  the  Lombardy  poplar 
by  its  wider  crown  and  its  more  open  branching,  Fig.  41. 
It  may  be  recognized  by  its  big  terminal  twigs,  wThich  are 
light  yellow  in  color  and  coarser  than  those  of  the  Lombardy 
poplar,  Fig.  42.  Its  bark  is  smooth,  light  and  yellowish- 
green  in  young  trees,  and  dark  gray  and  fissured  in  elder 
specimens.  Its  large,  conical,  glossy,  chestnut-brown  bud 
is  also  characteristic,  Fig.  42.  Its  flowers,  in  the  form 
of  large  catkins,  a  peculiarity  of  all  poplars,  appear  in  the 
early  spring.  The  Carolina  poplar  is  commonly  planted 
in  cities  because  it  grows  rapidly  and  is  able  to  withstand 
the  smoke  and  drouth  conditions  of  the  city.  Where  other 
trees,  however,  can  be  substituted  with  success,  the  poplar 
should  be  avoided.  Its  very  fast  growth  is  really  a  point 


52 


STUDIES  OF  TREES 


against  the  tree,  because  it  grows  so  fast  that  it  becomes 
too   tall   for   surrounding   property,    and   its    wood    being 


FIG.  41. — Carolina  Poplar. 

extremely  soft  and  brittle,  the  tree  frequently  breaks  in 
windstorms.  In  many  cases  it  is  entirely  uprooted,  because 
it  is  not  a  deep-rooted  tree.  Its  larger  roots,  which  spread 


TREES  TOLD  BY  THEIR  FORM 


53 


near  the  surface,  upset  the  sidewalk  or  prevent  the  growth 
of  other  vegetation  on  the  lawn,  while  its  finer  rootlets, 
in  their  eager  search  for  moisture, 
penetrate  and  clog  the  joints  of 
neighboring  water  and  sewer  pipes. 
The  tree  is  commonly  attacked  by 
the  oyster-shell  scale,  an  insect  which 
sucks  the  sap  from  its  bark  and  which 
readily  spreads  to  other  more  valuable 
trees  like  the  elm.  The  female  form 
of  this  tree  is  even  more  objectionable 
than  the  male,  because  in  the  early 
spring  the  former  produces  an  abun- 
dance of  cotton  from  its  seeds  which 
litters  the  ground  and  often  makes 
walking  dangerous.  The  only  justifi- 
cation for  planting  the  Carolina 
poplar  is  in  places  where  the  con- 
ditions for  tree  growth  are  so  poor 
that  nothing  else  will  grow,  and  in 
those  cases  the  tree  should  be  cut 
back  periodically  in  order  to  keep  it 
from  becoming  too  tall  and  scraggly. 
It  is  also  desirable  for  screening  in 
factory  districts  and  similar  situa- 
tions. 

The  silver  or  white  poplar  (Populus 
alba)  may  be  told  from  the  other 
poplars  by  its  characteristic  smooth, 
whitish-green  bark,  often  spotted  with 
dark  blotches,  Fig.  43.  The  leaves 
are  silvery-white  and  downy  on  the  under  side.  The  twigs 
are  dark  green  in  color  and  densely  covered  with  a  white 


FIG.  42.— Bud  of  the 
Carolina  Poplar. 


54 


STUDIES  OF  TREES 


down.  It  grows  to  very  large  size  and  forms  an  irregular, 
wide-spreading,  broad  head,  which  is  characteristically 
different  from  that  of  any  of  the  other  poplars. 

The  quaking  aspen  (Populus  tremuloides) ,  the  large- 
toothed  aspen  (Populus  grandidentata)  and  the  balsam  pop- 
lar or  balm  of  Gilead  (Populus  balsamifera)  are  other  com- 


FIG.  43.— Bark  of  the  Silver  Poplar. 

mon  members  of  the  poplar  group.  The  quaking  aspen 
may  be  told  by  its  reddish-brown  twigs,  narrow  sharp- 
pointed  buds,  and  by  its  small  finely  toothed  leaves.  The 
large-toothed  aspen  has  thicker  and  rather  downy  buds 
and  broader  and  more  widely  toothed  leaves.  The  balsam 
poplar  has  a  large  bud  thickly  covered  with  a  sticky,  pun- 
gent, gelatinous  substance. 


TREES    TOLD  BY  THEIR    FORM 


55 


GINGKO  OR  MAIDENHAIR  TEEE_(Gingko  bikba) 

Distinguishing  characters:    The  peculiar  branches   of 
this  tree  emerge  upward  from  a  straight  tapering  trunk 


FIG.  44.— Gingko  Trees. 

at  an  angle  of  about  45°  and  give  to  the  whole -tree  a  strik- 
ing, Oriental  appearance,  which  is  quite  different  from 
that  of  any  other  tree,  Fig.  44. 

Leaf:     Like  that  of  the  maidenhair  fern,  Fig.  45. 


56 


STUDIES   OF  TEEES 


Range:     A  native  of  northern  China  and  introduced 
into  eastern  North  America. 

Soil  and  location:    The  gingko  will  grow  in  poor  soils. 
Enemies:     Practically  free  from  insects  and  disease. 


FIG.  45. — Leaves  of  the  Gingko  Tree. 

Value  for  planting:  It  makes  a  valuable  tree  for  the 
street  where  heavy  shade  is  not  the  object  and  forms  an 
excellent  wide-spreading  specimen  tree  on  the  lawn. 

Other  characters :    The  fruit  consists  of  a  stone  covered 


TREES   TOLD  BY  THEIR  FORM 


57 


by  sweet,   ill-smelling  flesh.     The  tree  is  dioecious,  there 

being  separate  male  and  female  trees.     The  male  tree  is 

preferable    for    planting    in   order  to 

avoid   the   disagreeable  odor  of   the  * 

fruit  which   appears    on   the  female 

trees    when   about  thirty  years  old. 

The  male  tree  has  a  narrower  crown 

than  the  female  tree.     The  buds  (Fig. 

46)  are  very  odd  and  are  conspicuous 

on   the  tree   throughout  the  winter. 

The  leaves  of  the  gingko  shed  in  the 

winter.     In  this   respect   the  tree   is 

like  the  larch  and  the  bald  cypress. 

The  gingko  belongs  to  the  yew 
family,  which  is  akin  to  the  pine 
family.  It  is  therefore  a  very  old 
tree,  the  remains  of  the  forests  of 
the  ancient  world.  The  gingko  in  its 
early  life  is  tall  and  slender  with  its 
few  branches  close  to  the  stem.  But 
after  a  time  the  branches  loosen  up 
and  form  a  wide-spreading  crown. 
In  the  Orient  it  attains  enormous 
proportions  and  in  this  country  it 
also  grows  to  a  fairly  large  size  when 
planted  on  the  open  lawn  or  in  FIG.  46. — Bud  of 
groups  far  apart  from  other  trees  so  the  Gingko  Tree, 
that  it  can  have  plenty  of  room  to 
spread.  It  then  produces  a  picturesque  effect  of  unusual 
interest. 


58 


STUDIES   OF  TREES 


WEEPING  WILLOW  (Salix  babylonica) 

Distinguishing    characters:    All    the    willows    have    a 
single  cap-like  scale  to  the  bud,  and  this  species  has  an 


FIG.  47.— Weeping  Willow. 

unusually    drooping    mass    of    slender    branchlets    which 
characterizes  the  tree  from  all  others,  Fig.  47. 


TREES  TOLD  BY  THEIR  BARK  OR  TRUNK         59 

Form  and  size:    It  grows  to  large  size. 

Range:  Asia  and  Europe  and  naturalized  in  eastern 
United  States. 

Soil  and  location:  Prefers  moist  places  near  streams 
and  ponds. 

Enemies:     None  of  importance. 

Value  for  planting:  The  weeping  willow  has  a  special 
ornamental  effect  in  cemeteries  and  along  lakes  and  river 
banks  in  parks. 

Commercial  value:  It  is  used  in  the  United  States  for 
charcoal  and  for  fuel. 

Comparisons:  The  pussy  willow  (Salix  discolor)  may 
easily  be  told  from  the  other  willows  by  its  small  size; 
it  is  often  no  higher  than  a  tall  shrub.  Its  branches  are 
reddish  green  and  the  buds  are  dark  red,  smooth  and  glossy. 
The  predominating  color  of  the  twigs  and  buds  in  the  pussy 
willow  is  therefore  a  shade  of  red,  while  in  the  weeping 
willow  it  is  yellowish  green. 


GROUP  VII.  TREES  TOLD  BY  THEIR  BARK  OR  TRUNK: 
SYCAMORE,  BIRCH,  BEECH,  BLUE  BEECH,  IRON- 
WOOD,  AND  HACKBERRY 

How  to  tell  them  from  other  trees:  The  color  of  the 
bark  or  the  form  of  the  trunk  of  each  of  the  trees  in  this  group 
is  distinct  from  that  of  any  other  tree. 

How  to  tell  them  from  each  other:  In  the  sycamore, 
the  bark  is  mottled;  in  the  white  birch,  it  is  dull  white;  in 
the  beech,  it  is  smooth  and  gray;  in  the  hackberry,  it  is 
covered  with  numerous  corky  warts;  in  the  blue  beech,  the 
trunk  of  the  tree  is  fluted,  as  in  Fig.  54,  and  in  the  iron- 
wood,  the  bark  peels  in  thin  perpendicular  strips. 


60 


STUDIES  OF  TREES 


w. 


FIG.  48.— Bark  of  the  Sycamore  Tree. 

THE  SYCAMORE  OR  PLANE  TREE  (Platanus  occidentalis) 

Distinguishing  characters :  The  peculiar  mottled  appear- 
ance of  the  bark  (Fig.  48)  in  the  trunk  and  large  branches 
is  the  striking  character  here.  The  bark  produces  this 


TREES    TOLD   BY  THEIR  BARK  OR  TRUNK        61 

effect  by  shedding  in  large,  thin,  brittle  plates.     The  newly 
exposed  bark  is  of  a  yellowish  green  color  which  often  turns 


FIG.  49. — Seed-balls  of  the  Oriental  Sycamore. 
Note  one  Seed-ball  cut  in  half. 

nearly  white  later  on.     Round  seed  balls,  about  an  inch  in 
diameter,  may  be  seen  hanging  on  the  tree  all  winter.     In 


62 


STUDIES  OF  TREES 


this  species,  the  seed  balls  are  usually  solitary,  while  in  the 
Oriental  sycamore,  a  European  tree  similar  to  the  native 

one,  they  appear  in  clusters 
of  two,  or  occasionally  of 
three  or  four.  See  Fig.  49. 

Leaf:  The  stem  of  the 
leaf  completely  covers  the 
bud.  This  is  a  characteris- 
tic peculiar  to  sycamores. 

Form  and  size:  A  large 
tree  with  massive  trunk  and 
branches  and  a  broad  head. 

Range  :  Eastern  and 
southern  United  States. 

Soil  and  location:  Pre- 
fers a  deep  rich  soil,  but  will 
adapt  itself  even  to  the  poor 
soil  of  the  city  street.- 

Enemies:  The  sycamore 
is  frequently  attacked  by  a 
fungus  (Gloeosporium  nervise- 
quum),  which  curls  up  the 
young  leaves  and  kills  the 
tips  of  the  branches.  Late 
frosts  also  often  injure  its 
young  twigs.  The  Oriental 
sycamore,  which  is  the  Euro- 
FIG.  60.— Gray  or  White  Birch  Pean  species,  is  mere  hardy 
Trees.  in  these  respects  than  the 

native  one  and  is  therefore 
often    chosen    as   a    substitute. 

Value  for  planting:    The  Occidental  sycamore  is  now 


TREES  TOLD  BY  THEIR  BARK  OR  TRUNK        63 


planted  very  little,  but  the  Oriental  sycamore  is  used  quite 
extensively  in  its  place,  especially  as  a  shade  tree.  The 
Oriental  sycamore  is 
superior  to  the  native 
species  in  many  ways. 
It  is  more  shapely, 
faster  growing,  and 
hardier  than  the  na- 
tive one.  Both  syca- 
mores will  bear  trans- 
planting and  pruning 
well. 

Commercial  value : 
The  wood  of  the  syca- 
more is  coarse-grained 
and  hard  to  work; 
used  occasionally  for 
inside  finishing  in 
buildings. 

Other  names  :But- 
tonball,  buttonwood. 

Comparisons:  The 
Oriental  sycamore 
(Platanus  orientalis) 
an  introduced  species, 
is  apt  to  be  confused 
with  the  Occidental 
sycamore,  but  may 
be  told  from  the  lat- 
ter by  the  number  of 
seed  balls  suspended 

from  the  tree.     In  the  case  of  the  Oriental  species,  the 
seed  balls  hang  in  pairs  or  (rarely)  three  or  four  together. 


FIG.  51.— Bark  of  the  Black  or  Sweet 
Birch. 


64  STUDIES  OF  TREES 

In  the  Occidental,  the  seed  balls  are  generally  solitary  and 
very  rarely  in  pairs. 

GRAY  OR  WHITE  BIRCH  (Betula  populifolia) 

Distinguishing  characters:  The  dull-white  color  of 
the  bark  on  the  trunk  and  the  dark  triangular  patches  below 
the  insertion  of  the  branches  distinguish  this  tree;  see  Fig. 
50.  The  bark  of  the  young  trunks  and  branches  is  red- 
dish-brown in  color  and  glossy.  The  bark  adheres  closely 
to  the  trunk  of  the  tree  and  does  not  peel  in  loose,  shaggy 
strips,  as  in  the  case  of  the  yellow  or  golden  birch.  It  is 
marked  by  small  raised  horizontal  lines  which  are  the 
lenticels  or  breathing  pores.  These  lenticels  are  char- 
acteristic of  all  birch  and  cherry  trees.  In  addition  to  the 
distinction  in  the  color  of  the  bark,  an  important  char- 
acter which  distinguishes  the  gray  birch  from  all  other 
species  of  birch,  is  found  in  the  terminal  twigs,  which  are 
rough  to  the  touch. 

Form  and  size:  A  small  tree.  Frequently  grows  in 
clumps. 

Range:     Eastern  United  States. 

Soil  and  location:  The  gray  birch  does  best  in  a  deep, 
rich  soil,  but  will  also  grow  in  poor  soils. 

Enemies:  The  bronze-birch  borer,  a  wood-destroying 
insect,  and  Polyporus  betulinus,  a  fungus,  are  its  chief 
enemies. 

Value  for  planting:  Its  graceful  habit  and  attractive 
bark  gives  the  tree  an  important  place  in  ornamental  plant- 
ing. It  may  be  used  to  advantage  with  evergreens,  and  pro- 
duces a  charming  effect  when  planted  by  itself  in  clumps. 


TREES  TOLD  BY  THEIR  BARK  OR  TRUNK         65 


FIG.  52.— Bark  of  the  Beech, 


66 


STUDIES  OF  TREES 


Commercial  value: 
The  wood  is  soft  and 
not  durable.  It  is  used 
in  the  manufacture  of 
small  articles  and  for 
wood  pulp. 

Other  characters  : 
The  fruit  is  a  catkin. 

Comparisons :  The 
paper  birch  (Betula 
papyri/era)  is  apt  to 
be  confused  with  the 
gray  birch,  because 
both  have  a  white 
bark.  The  bark  of  the 
paper  birch,  however, 
is  a  clear  white  and 
peels  off  in  thin  papery 
layers  instead  of  being 
close.  It  very  seldom 
shows  any  dark  tri- 
angular markings  on 
the  trunk.  Its  terminal 
twigs  are  not  rough 
and  its  trunk  is  usually 
straighter  and  freer 
from  branches. 

The  black  or  sweet 
birch  (Betula  lento)  has 
a  bark  similar  to  the 
gray  birch,  except  that 
its  color  is  dark  gray.  See  Fig.  51.  The  twigs  have  an 
aromatic  taste. 


FIG.  53.— Buds  of  the  Beech  Tree. 


TREES  TOLD  BY  THEIR  BARK  OR  TRUNK    67 


FIG.  54. — Trunk  of  Blue 
Beech, 


FIG.  55. — Bark  of  the  Ironwood. 


68  STUDIES  OF  TREES 

The  yellow  birch  (Betula  lutea)  has  a  yellowish  or  golden 
bark  which  constantly  peels  in  thin,  ragged,  horizontal 
films. 

The  European  white  birch  (Betula  alba)  has  a  dull-white 
bark  like  the  native  white  birch,  but  has  smooth  terminal 
twigs  instead  of  rough  ones.  It  is  commonly  seen  in  the 
United  States  on  lawns  and  in  parks. 

AMERICAN  BEECH  (Fagus  americana) 

Distinguishing  characters:  The  close-fitting,  smooth, 
gray  ba!rk  will  tell  this  tree  from  all  others  except  the  red 
maple  and  yellow-wood.  See  Fig.  52.  The  red  maple 
may  then  be  easily  eliminated  by  noting  whether  the 
branches  are  alternate  or  opposite.  They  are  alternate 
in  the  beech  and  opposite  in  the  maple.  The  yellow-wood 
may  be  eliminated  by  noting  the  size  of  the  bud.  The 
bud  in  the  yellow-wood  is  hardly  noticeable  and  of  a  golden 
yellow  color,  while  that  of  the  beech  is  very  long,  slender, 
and  sharp-pointed,  and  chestnut  brown  in  color.  See 
Fig.  53. 

Form  and  size:  It  grows  tall  in  the  woods,  but  on  the 
open  lawn  spreads  out  into  a  massive,  round-headed  tree. 

Range:    Eastern  Canada  and  United  States. 

Soil  and  location:  Prefers  a  rich,  well-drained  soil, 
but  will  grow  in  any  good  soil. 

Enemies:  Aphides  or  plant  lice  that  suck  the  sap  from 
the  leaves  in  spring  and  early  summer  are  the  chief  enemies 
of  the  tree. 

Value  for  planting:  The  pleasing  color  of  its  bark, 
its  fine  spread  of  branches,  which  gracefully  droop  down 


TREES  TOLD  BY  THEIR  BARK  OR  TRUNK 


69 


to  the  ground,  and  its  autumnal  coloring,  make  the  beech 
a  favorite  for  lawn  and  park  planting.  The  several  Euro- 
pean species  of  beech  are  equally  charming. 

Commercial  value  : 
The  wood  is  strong, 
close-grained,  and  tough. 
It  is  used  mainly  for 
cooperage,  tool  handles, 
shoe  lasts,  chairs,  etc., 
and  for  fuel. 

Other  characters : 
The  fruit  is  a  prickly 
burr  encasing  a  sharply 
triangular  nut  which  is 
sweet  and  edible. 

Comparisons  :  The 
European  beech  (Fagus 
sylvatica),  and  its  weep- 
ing, purple-leaved,  and 
fern-leaved  varieties,  are 
frequently  met  with  in 
parks  and  may  be  told 
from  the  native  species 
by  its  darker  bark.  The 
weeping  form  may,  of 
course,  be  told  readily 
by  its  drooping  branches. 
The  leaves  of  the  European  beeches  are  broader  and  less 
serrated  than  those  of  the  American  beech. 


FIG.  56.— Bark  of  the  Hackberry. 


70  STUDIES   OF  TREES 

BLUE  BEECH  OR  HORNBEAM  (Carpinus  caroliniana) 

Distinguishing  characters :  The  fluted  or  muscular  effect 
of  its  trunk  will  distinguish  the  tree  at  a  glance,  Fig.  54. 

Leaf:  Doubly  serrated;  otherwise  the  same  as  that  of 
ironwood. 

Form  and  size:  A  low-spreading  tree  with  branches 
arching  out  at  various  angles,  forming  a  flattened  head 
with  a  fine,  slender  spray. 

Range:    Very  common  in  the  eastern  United  States. 

Soil  and  location :    Grows  in  low  wet  woods. 

Enemies:     None  of  importance. 

Value  for  planting:  Its  artistic  branching  and  curious 
trunk  give  the  tree  an  important  place  in  park  planting. 

Commercial  value:    None. 

Other  characters:  The  bark  is  smooth  and  bluistT gray 
in  color. 

Comparisons:  The  blue  beech  or  hornbeam  is  often  con-" 
fused  with  the  ironwood  or  hop  hornbeam  (Ostrya  virginiana) . ' 
The  ironwood,  however,  has  a  characteristic  bark  that  peels 
in  perpendicular,  short,  thin  segments,  often  loose  at  the 
ends.  See  Fig.  55.  This  is  entirely  different  from  the  close, 
smooth,  and  fluted  bark  of  the  blue  beech.  The  color  of 
the  bark  in  the  ironwood  is  brownish,  while  that  of  the 
blue  beech  is  bluish-gray.  The  buds  of  the  ironwood 
are  greenish  with  brown  tips,  while  the  bud  of  the  blue 
beech  shows  no  green  whatever. 

HACKBERRY  (Celtis  occidentalis) 

Distinguishing  characters:  The  tree  may  be  told 
readily  from  other  trees  by  the  corky  tubercles  on  the 
bark  of  the  lower  portion  of  the  trunk.  See  Fig.  56. 


THE  OAKS  AND  CHESTNUT  71 

Leaf:  Has  three  predominating  veins  and  is  a  bit 
more  developed  on  one  side  than  on  the  other. 

Form  and  size:  A  small  or  medium-sized  tree  with 
a  single  stem  and  broad  conical  crown. 

Range:    United  States  and  Canada. 

Soil  and  location:  Grows  naturally  in  fertile  soils,  but 
will  adapt  itself  to  almost  sterile  soils  as  well. 

Enemies:  The  hackberry  is  usually  free  from  disease, 
though  often  its  leaves  are  covered  with  insect  galls. 

Value  for  planting:  It  is  extensively  planted  as  a  shade 
tree  in  the  Middle  West,  and  is  frequently  seen  as  an  orna- 
mental tree  in  the  East. 

Commercial  value:  It  has  little  economic  value  except 
for  fuel. 

Other  characters :  The  fruit  is  berry-like,  with  a  hard 
pit.  The  fleshy  outer  part  is  sweet. 

Other  common  names:    Nettle  tree:  sugarberry. 

GROUP  VIII.     THE  OAKS  AND  CHESTNUT 

How  to  tell  them  from  other  trees:  The  oaks  are 
rather  difficult  to  identify  and,  in  studying  them  it  will 
often  be  necessary  to  look  for  more  than  one  distinguishing 
character.  The  oaks  differ  from  other  trees  in  bearing 
acorns.  Their  leaves  have  many  lobes  and  their  upper 
lateral  buds  cluster  at  the  top  of  the  twigs.  The  general 
contour  of  each  oak  presents  a  characteristic  branching 
and  sturdiness  uncommon  in  other  trees. 

The  chestnut  differs  from  other  trees  in  bearing  burs 
and  its  bark  is  also  distinctly  characteristic. 

How  to  tell  them  from  from  each  other:  There  are 
two  groups  of  oaks,  the  white  oak  and  the  black  oak.  The 
white  oaks  mature  their  acorns  in  one  year  and,  there- 


72 


STUDIES   OF  TREES 


fore,  only  acorns  of  the  same  year  can  be  found  on  trees  of 
this  group.  The  black  oaks  take  two  years  in  which  to  ma- 
ture their  acorns  and,  therefore,  young  acorns  of  the  present 

year  and  mature  acorns  of 
the  previous  year  may  be 
found  on  the  same  tree  at 
one  time.  The  leaves  of  the 
white  oaks  have  rounded 
margins  and  rounded  lobes 
as  in  Fig.  57,  while  those 
of  the  black  oaks  have 
pointed  margins  and  sharp 
pointed  lobes  as  shown  in 
Figs.  60,  62  and  64.  The 
bark  of  the  white  oaks  is 
light  colored  and  breaks 
up  in  loose  flakes  as  in  Fig. 
58,  while  that  of  the  black 
oaks  is  darker  and  deeply 
ridged  or  tight  as  in  Figs. 
59  and  61.  The  white  oak 
is  the  type  of  the  white 


FIG.  57.— Leaf  and  Fruit  of  White 
Oak.     (Quercus  alba.) 


acterization   of    the   individual   species, 
ferred  to  the  following  pages, 


oak  group  and  the  black, 
red  and  pin  oaks  are  types 
of  the  other.  For  the  char- 
the  reader  is  re- 


WHITE  OAK  (Quercus  alba) 

Distinguishing  characters:  The  massive  ramification 
of  its  branches  is  characteristic  of  this  species  and  often 
an  easy  clue  to  its  identification.  The  bark  has  a  light 


THE  OAKS   AND  CHESTNUT 


73 


gray  color — lighter  than 
that  of  the  other  oaks — 
and  breaks  into  soft, 
loose  flakes  as  in  Fig.  58. 
The  leaves  are  deeply 
lobed  as  in  Fig.  57. 
The  buds  are  small, 
round  and  congested  at 
the  end  of  the  year's 
growth.  The  acorns 
usually  have  no  stalks 
and  are  set  in  shallow, 
rough  cups.  The  kernels 
of  the  acorns  are  white 
and  palatable. 

Form  and  size:  The 
white  oak  grows  into  a 
large  tree  with  a  wide- 
spreading,  massive 
crown,  dissolving  into 
long,  heavy,  twisted 
branches.  When  grown 
in  the  open  it  possesses 
a  short  sturdy  trunk;  in 
the  forest  its  trunk  is 
tall  and  stout. 

Range  :  Eastern 
North  America. 

Soil  and  location:  The  white  oak  thrives  in  almost 
any  well-drained,  good,  deep  soil  except  in  a  very  cold  and 
wet  soil.  It  requires  plenty  of  light  and  attains  great  age. 


FIG.  58.— Bark  of  White  Oak. 
(Quercus  alba.) 


74 


STUDIES  OF  TREES 


1   / 


Enemies:  The  tree  is  comparatively  free  from  insects 
and  disease  except  in  districts  where  the  Gipsy  moth  is 
common,  in  which  case  the  leaves  of  the  white  oak  are  a 
favorite  food  of  its  caterpillars. 

Value  for  planting  : 
The  white  oak  is  one  of 
the  most  stately  trees. 
Its  massive  form  and  its 
longevity  make  the  tree 
suitable  for  both  lawn 
and  woodland  planting 
but  it  is  not  used  much 
because  it  is  difficult  to 
transplant  and  grows 
rather  slowly. 

Commercial  value  : 
The  wood  is  of  great 
economic  importance.  It 
is  heavy,  hard,  strong  and 
durable  and  is  used  in 
cooperage,  construction 
work,  interior  finish  of 
FIG.  59.-Bark  of  Black  Oak.  buildings  and  for  railroad 

(Quercus  velutina).  ties,     furniture,     agricul- 

tural implements  and  fuel. 

Comparisons:.  The  swamp  white  oak  (Quercus  plata- 
noides)  is  similar  to  the  white  oak  in  general  appearance 
of  the  bark  and  form  and  is  therefore  liable  to  be  confused 
with  it.  It  differs  from  the  white  oak,  however,  in  pos- 
sessing a  more  straggly  habit  and  in  the  fact  that  the  bark 
on  the  under  side  of  its  branches  shags  in  loose,  large 
scales.  Its  buds  are  smaller,  lighter  colored  and  more 
downy  and  its  acorns  are  more  pointed  and  with  cups 


THE   OAKS  AND  CHESTNUT 


75 


more  shallow  than  those  of  the  white  oak.      The  tree  also 
grows  in  moister  ground,  generally  bordering  swamps. 


FIG.  60.— Leaf  and  Fruit  of  Black  Oak. 
(Quercus  velutina). 

BLACK  OAK  (Quercus.  velutina) 

Distinguishing  characters:  The  bark  is  black,  rough 
and  cut  up  into  firm  ridges  especially  at  the  base  of  the 
tree,  see  Fig.  59.  The  inner  bark  has  a  bright  yellow  color: 
the  leaves  have  sharp  points  and  are  wider  at  the  base 
than  at  the  tip  as  shown  in  Fig.  60.  The  buds  are  large, 
downy  and  sharp  pointed.  The  acorns  are  small  and  have 


76  STUDIES  OF  TREES 

deep,  scaly  cups  the  inner  margins  of  which  are  downy. 
The  kernels  are  yellow  and  bitter. 

Form  and  size:  The  tree  grows  in  an  irregular  form 
to  large  size,  with  its  branches  rather  slender  as  compared 
with  the  white  oak  and  with  a  more  open  and  narrow 
crown. 

Range:     Eastern  North  America. 

Soil  and  location:  It  will  grow  in  poor  soils  but  does 
best  where  the  soil  is  rich  and  well  drained. 

Enemies:    None  of  importance. 

Value  for  planting:  The  black  oak  is  the  poorest  of  the 
oaks  for  planting  and  is  rarely  offered  by  nurserymen. 

Commercial  value :  The  wood  is  heavy,  hard  and  strong, 
but  checks  readily  and  is  coarse  grained.  It  is  of  little 
value  except  for  fuel.  The  bark  is  used  for  tannin. 

Other  common  names:     Yellow  oak. 

Comparisons:  The  black  oak  might  sometimes  be 
confused  with  the  red  and  scarlet  oaks.  The  yellow,  bitter 
inner  bark  will  distinguish  the  black  oak  from  the  other 
two.  The  light-colored,  smooth  bark  of  the  red  oak  and 
the  dark,  ridged  bark  of  the  black  oak  will  distinguish 
the  two,  while  the  bark  of  the  scarlet  oak  has  an  appear- 
ance intermediate  between  the  two.  The  buds  of  the  three 
species  also  show  marked  differences.  The  buds  of  the 
black  oak  are  covered  with  hairs,  those  of  the  scarlet  oak 
have  fewer  hairs  and  those  of  the  red  are  practically  free 
from  hairs.  The  leaves  of  each  of  the  three  species  are 
distinct  and  the  growth  habits  are  different. 

RED  OAK  (Quercus  rubra) 

Distinguishing  characters:  The  bark  is  perpendicularly 
fissured  into  long,  smooth,  light  gray  strips  giving  the  trunk 


THE  OAKS  AND  CHESTNUT 


77 


a  characteristic  pillar  effect  as  in  Figs.  61  and  94.  It  has 
the  straightest  trunk  of  all  the  oaks.  The  leaves  possess 
more  lobes  than  the  leaves 
of  any  of  the  other 
species  of  the  black  oak 
group,  see  Fig.  62.  The 
acorns,  the  largest  among 
the  oaks,  are  semispheri- 
cal  with  the  cups  ex- 
tremely shallow.  The 
buds  are  large  and  sharp 
pointed,  but  not  as  large 
as  those  of  the  black 
oak.  They  also  have  a 
few  fine  hairs  on  their 
scales,  but  are  not  nearly 
as  downy  as  those  of  the 
black  oak. 

Form  and  size:  The 
red  oak  is  the  largest 
of  the  oaks  and  among 
the  largest  of  the  trees 
in  the  northern  forests. 
It  has  a  straight  trunk, 
free  from  branches  to  a 
higher  point  than  in  the 
white  oak,  see  Fig.  94.  FIG.  61.— Bark  of  Red  Oak. 

The    branches    are    less 

twisted   and  emerge   at  sharper  angles   than  do  those  of 
the  white  oak. 


78 


STUDIES   OF  TREES 


Range:    It  grows  all  over  Eastern  North  America   and 
reaches  north  farther  than  any  of  the  other  oaks. 

Soil  and  location:     It  is  less  fastidious  in  its  soil  and 
moisture  requirements  than  the  other  oaks  and  therefore 

grows  in  a  great  variety 
of  soils.  It  requires  plenty 
of  light. 

Enemies:  Like  most 
of  the  other  oaks,  this 
species  is  comparatively 
free  from  insects  and  dis- 
ease. 

Value  for  planting : 
The  red  oak  grows  faster 
and  adapts  itself  better 
to  poor  soil  conditions 
than  any  of  the  other 
oaks  and  is  therefore  easy 
to  plant  and  easy  to  find 
in  the  nurseries.  It  makes 
an  excellent  street  tree,  is 
equally  desirable  for  the 
lawn  and  is  hardly  sur- 
passed  for  woodland 
planting. 

Commercial    value  : 

The  wood  is  hard  and  strong  but  coarse  grained,  and  is 
used  for  construction  timber,  interior  finish  and  furniture. 
It  is  inferior  to  white  oak  where  strength  and  durability 
are  required. 


FIG.  62.— Leaf  and  Fruit  of  Red 
Oak. 


THE  OAKS  AND   CHESTNUT 


79 


PIN  OAK  (Quercus  palustris) 

Distinguishing  characters:  Its  method  of  branching 
will  characterize  the  tree  at  a  glance.  It  develops  a  well- 
defined  main  ascending  stem  with  numerous  drooping  side 
branches  as  in  Fig.  63.  The  buds 
are  very  small  and  sharp  pointed 
and  the  leaves  are  small  as  in 
Fig.  64.  The  bark  is  dark,  firm, 
smooth  and  in  close  ridges.  The 
acorn  is  small  and  carries  a  light 
brown,  striped  nut,  wider  than 
long  and  bitter.  The  cup  is 
shallow,  enclosing  only  the  base 
of  the  nut. 

Form  and  size:  The  pin  oak 
is  a  medium-sized  tree  in  com- 
parison with  other  oaks.  It  de- 
velops a  tall,  straight  trunk  that 
tapers  continuously  through  a 
pyramidal  crown  of  low,  droop- 
ing tender,  branches. 

Range :  Eastern  North 
America. 

Soil  and  location :  It  requires 
a  deep,  rich,  moist  soil  and  grows 
naturally  near  swamps.     Its  roots  are  deep  and  spreading. 
The  tree  grows  rapidly  and  is  easily  transplanted. 

Enemies:    None  of  importance. 

Value  for  planting :    The  pin  oak  is  an  extremely  grace- 
ful tree  and  is  therefore  extensively  used  for  planting  on 


FIG.   63. — Pin  Oaks  in 
Winter. 


80 


STUDIES  OF  TREES 


lawns  and  on  certain  streets  where  the  tree  can  find  plenty 

of  water  and  where  conditions  will  permit  its  branches  to 

droop  low. 

Commercial  value:    The  wood  is  heavy  and  hard  but 

coarse  grained  and  liable  to  check  and  warp.     Its  principal 

use   is   in  the  construction  of 
houses  and  for  shingles. 

CHESTNUT  (Castanea  dentata) 

Distinguishing  characters : 
The  bark  in  young  trees  is 
smooth  and  of  a  marked  red- 
dish-bronze color,  but  when  the 
tree  grows  older,  the  bark 
breaks  up  into  diamond-shaped 
ridges,  sufficiently  characteris- 
tic to  distinguish  the  tree  at  a 
glance,  see  Fig.  65.  A  close 
examination  of  the  terminal 
twig  will  show  three  ridges  and 
two  grooves  running  down  along 
the  stem  from  the  base  of  each 
leaf  or  leaf-scar.  The  twig  has 
no  true  terminal  bud.  The 

fruit,  a  large,  round  bur,  prickly  without  and  hairy  within 

and  enclosing  the  familiar  dark  brown,  sweet  edible  nuts 

is  also  a  distinguishing  mark  of  the  tree. 

Leaf:    The    leaves    are    distinctly    long    and    narrow. 

They  are  from  6  to  8  inches  long. 


FIG.  64.— Leaf  and  Fruit  of 
Pin  Oak. 


THE  OAKS  AND  CHESTNUT 


81 


Form  and  size:  The  chestnut  is  a  large  tree  with 
a  massive  trunk  and  broad  spreading  crown.  The  chest- 
nut tree  when  cut,  sprouts  readily  from  the  stump  and 


r 


FIG.  65.— Trunk  of  Chestnut  Tree. 

therefore  in  places  where  the  trees  have  once  been  cut, 
a  group  of  two  to  six  trees  may  be  seen  emerging  from  the 
old  stump. 

Range:     Eastern  United  States. 


82  STUDIES  OF  TREES 

Soil  and  location:  It  will  grow  on  rocky  as  well  as  on 
fertile  soils  and  requires  plenty  of  light. 

Enemies:  During  the  past  nine  years  nearly  all  the 
chestnut  trees  in  the  United  States  have  been  attacked 
by  a  fungus  disease  (Diaporthe  parasitica,  Mur.)  which 
still  threatens  the  entire  extinction  of  the  chestnut  trees 
in  this  country.  No  remedy  has  been  discovered  and 
all  affected  trees  should  be  cut  down  and  the  wood  utilized 
before  it  decays  and  becomes  worthless.  No  species  of 
chestnut  tree  is  entirely  immune  from  this  disease,  though 
some  species  are  highly  resistant. 

Value  for  planting:  The  chestnut  is  one  of  the  most 
rapidly  growing  hardwood  trees  but,  on  account  of  its 
disease,  which  is  now  prevalent  everywhere,  it  is  not  wise 
to  plant  chestnut  trees  for  the  present. 

Commercial  value:  The  wood  is  light,  not  very  strong 
and  liable  to  warp.  It  is  durable  when  brought  in  contact 
with  the  soil  and  is  therefore  used  for  railroad  ties,  fence- 
posts,  poles,  and  mine  timbers.  It  is  also  valuable  for 
interior  finish  in  houses  and  for  fuel.  Its  bark  is  used  in 
the  manufacture  of  tanning  extracts  and  the  nuts  are  sold 
in  cities  in  large  quantities. 


CHAPTER  III 
HOW  TO  IDENTIFY  TREES— (Continued) 

GROUP  IX.     THE  HICKORIES,  WALNUT  AND 
BUTTERNUT 

How  to  tell  them  from  other  trees  and  from  each  other: 

The  hickory  trees ,  though  symmetrical,  have  a  rugged 
appearance  and  the  branches  are  so  sturdy  and  black  as  to 
give  a  special  distinction  to  this  group.  The  buds  are 
different  from  the  buds  of  all  other  trees  and  sufficiently 
characteristic  to  distinguish  the  various  species  of  the 
group.  The  bark  is  also  a  distinguishing  character. 

The  walnut  and  butternut  have  chambered  piths  which 
distinguish  them  from  all  other  trees  and  from  each  other. 


SHAGBARK  HICKORY  (Hicoria  ovata) 

Distinguishing  characters:  The  yellowish  brown  buds 
nearly  as  large  as  those  of  the  mockernut  hickory,  are 
each  provided  with  two  long,  dark,  outer  scales  which  stand 
out  very  conspicuously  as  shown  in  Fig.  67.  The  bark 
in  older  specimens  shags  off  in  rough  strips,  sometimes 
more  than  a  foot  long,  as  shown  in  Fig.  68.  These  two 
characters  will  readily  distinguish  the  tree  at  all  seasons 
of  the  year. 

83 


84 


STUDIES  OF  TREES 


FIG.  66.— A  Shagbark  Hickory  Tree. 


THE  HICKORIES,  WALNUT  AND  BUTTERNUT      85 


Leaf:   The  leaf  is  compound,  consisting  of  5  or  7  leaflets, 
the  terminal  one  generally  larger. 

Form   and   size:    A   tall,   stately   tree — the   tallest   of 
the  hickories — of  rugged  form  and  fine 
symmetry,  see  Fig.  66. 

Range:     Eastern  North  America. 

Soil  and  location:  The  shagbark 
hickory  grows  in  a  great  variety  of 
soils,  but  prefers  a  deep  and  rather 
moist  soil. 

Enemies:  The  hickory  bark  borer 
(Scolytus  quadrispinosus)  is  its  principal 
enemy.  The  insect  is  now  killing 
thousands  of  hickory  trees  in  the  vicin- 
ity of  New  York  City  and  on  several 
occasions  has  made  its  appearance  in 
large  numbers  in  other  parts  of  the 
country. 

Value  for  planting:  It  is  difficult 
to  transplant,  grows  slowly  and  is  seldom 
found  in  nurseries. 

Commercial  value:  The  wood  is 
extremely  tough  and  hard  and  is  used 
for  agricultural  implements  and  for  the 
manufacture  of  wagons.  It  is  excellent 
for  fuel  and  the  nuts  are  of  great  value 
as  a  food. 

Other  characters :    The  fruit  is  a  nut 
covered  by  a  thick  husk  that  separates  into 
ments.     The  kernel  is  sweet. 

Other  common  names:    Shellbark  hickory. 


FIG.  67.— Bud  of  the 
Shagbark  Hickory. 


or  5  seg- 


86 


STUDIES  OF  TREES 


MOCKERNUT  HICKORY  (Hicoria  alba) 

Distinguishing  characters:  The  bud  is  the  largest 
among  the  hickories — nearly  half  an  inch  long — is  hard 
and  oval  and  covered  with  yellowish 
brown  downy  scales  which  do  not  pro- 
ject like  those  of  the  shagbark  hickory, 
see  Fig.  69.  The  twigs  are  extremely 
coarse.  The  bark  is  very  tight  on  the 
trunk  and  branches  and  has  a  close, 
hard,  wavy  appearance  as  in  Fig.  70. 

Leaf:  The  leaf  consists  of  5,  7  or  9 
leaflets  all  of  which  are  large  and  pubes- 
cent and  possess  a  distinct  resinous 
odor. 

Form  and  size:  A  tall  tree  with 
a  broad  spreading  head. 

Range:     Eastern  North  America. 

Soil  and  location:  The  mockernut 
hickory  grows  on  a  great  variety  of 
soils,  but  prefers  one  which  is  rich  and 
well-drained. 

Enemies:    The    same    as     for     the 
FIG.  68. — Bark  of       .  ... 

the  Shagbark  Hick-     shagbark  hickory. 

ory.  Value  for  planting:    It  is  not  com- 

monly planted. 

Commercial  value:    The  wood  is  similar  to  that  of  the 
shagbark  hickory  and  is  put  to  the  same  uses. 

Other  characters:     The  fruit  is  a  nut,  larger  and  cov- 
ered with  a  shell  thicker  than  that  of  the  shagbark.     The 


THE  HICKORIES,  WALNUT  AND  BUTTERNUT     87 


husk  is  also  thicker  and  separates 
into  four  segments  nearly  to  the 
base.  The  kernel  is  small  and  sweet. 

Other  common  names:  Big- 
bud  hickory;  whiteheart  hickory. 

Comparisons :  The  pignut  hick- 
ory (Hicoria  glabra),  sometimes 
called  broom  hickory  or  brown 
hickory,  often  has  a  shaggy  bark, 
but  differs  from  both  the  shag- 
bark  and  the  mockernut  hickory 
in  possessing  buds  very  much 
smaller,  twigs  more  slender  and 
leaflets  fewer.  The  nut  has  a 
thinner  husk  which  does  not  sep- 
arate into  four  or  five  segments. 
The  tree  prefers  drier  ground  than 
the  other  hickories. 

The  bitternut  (Hicoria  min- 
ima) can  be  told  from  the  mock- 
ernut and  other  species  of  hickory 
by  its  bud,  which  has  no  scales  at 
all.  The  color  of  its  bud  is  a 
characteristic  orange  yellow.  The 
bark  is  of  a  lighter  shade  than  the 
bark  of  the  mockernut  hickory 
and  the  leaflets  are  more  numerous  than  in  any  of  the 
hickories,  varying  from  7  to  11.  Its  nuts  are  bitter. 

BLACK  WALNUT  (Juglans  nigrd) 

Distinguishing  characters:     By  cutting  a  twig  length- 
wise,  it  will  be  seen  that  its  pith  is  divided  into  little 


FIG.  69. — Bud  of  the 
Mockernut  Hickory. 


88 


STUDIES  OF  TREES 


chambers  as  shown  in  Fig.  71.  The  bud  is  dark  gray  and 
satiny.  The  bark  is  dark  brown  and  deeply  ridged  and  the 
fruit  is  the  familiar  round  walnut. 

Form  and  size:    A  tall  tree  with  a  spreading  crown 
composed    of    stout    branches.     In    the 
open  it  grows  very  symmetrically. 
Range:     Eastern  United  States. 
Soil  and    location:    The  black  wal- 
nut prefers  a  deep,  rich,  fertile  soil  and 
requires  a  great  deal  of  light. 

Enemies:  The  tree  is  a  favorite  of 
many  caterpillars. 

Value  for  planting:  It  forms  a 
beautiful  spreading  tree  on  open  ground, 
but  is  not  planted  to  any  extent  because 
it  is  hard  to  transplant.  It  grows  slowly 
unless  the  soil  is  very  deep  and  rich, 
develops  its  leaves  late  in  the  spring 
and  sheds  them  early  in  the  fall  and 
produces  its  fruit  in  great  profusion. 

Commercial    value:    The    wood    is 
heavy,  strong,  of  chocolate  brown  color 
and  capable  of  taking  a  fine  polish.     It 
is  used  for  cabinet  making  and  interior 
finish   of   houses.     The   older  the  tree, 
usually,  the  better  the  wood,  and  the 
consumption  of   the  species  in  the  past 
has  been  so  heavy  that  it  is  becoming 
rare.     The  European  varieties  which  are  frequently  planted 
in  America    as    substitutes    for    the    native    species  yield 
better  nuts,  but  the  American  species  produces  better  wood. 
Other  characters :     The  fruit  is  a  large  round  nut  about 
two  inches  in  diameter,  covered  with  a  smooth  husk  which 


FIG.  70. — Bark  of 

the  Mockernut 

Hickory. 


THE  HICKORIES,  WALNUT  AND  BUTTERNUT      8' 


FIG.  71.— Twig  of  the 
Black  Walnut.  Note  the 
iarge  chambers  in  the  pith. 


FIG.  72.— Twig  of  the  But- 
ternut. Note  the  small 
chambers  in  the  pith. 


90  STUDIES  OF  TKEES 

at  first  is  dull  green  in  color  and  later  turns  brown.  The 
husk  does  not  separate  into  sections.  The  kernel  is  edible 
and  produces  an  oil  of  commercial  value. 

The  leaves  are  compound  and  alternate  with  15  to  23 
leaflets  to  each. 

Comparisons:  The  butternut  (Juglans  cinerea)  is  an- 
other tree  that  has  the  pith  divided  into  little  chambers, 
but  the  little  chambers  here  are  shorter  than  in  the  black 
walnut,  as  may  be  seen  from  a  comparison  of  Figs.  71 
and  72.  The  bark  of  the  butternut  is  light  gray  while  that 
of  the  black  walnut  is  dark.  The  buds  in  the  butternut 
are  longer  than  those  of  the  black  walnut  and  are  light 
brown  instead  of  gray  in  color.  The  form  of  the  tree  is 
low  and  spreading  as  compared  with  the  black  walnut. 
The  fruit  in  the  butternut  is  elongated  while  that  of  the 
black  walnut  is  round.  The  leaves  of  the  butternut  have 
fewer  leaflets  and  these  are  lighter  in  color. 


GROUP  X.  TULIP  TREE,  SWEET  GUM,  LINDEN,  MAG- 
NOLIA, LOCUST,  CATALPA,  DOGWOOD,  MUL- 
BERRY AND  OSAGE  ORANGE 

TULIP  TREE  (Liriodendron  tulipifera) 

Distinguishing  characters:  There  are  four  characters 
that  stand  out  conspicuously  in  the  tulip  tree — the  bud, 
the  trunk,  the  persistent  fruit  cups  and  the  wedged  leaf. 

The  bud,  Fig.  74,  about  an  inch  long,  is  covered  by  two 
purplish  scales  which  lend  special  significance  to  its  whole 
appearance.  The  trunk  is  extremely  individual  because  it 
rises  stout  and  shaft-like,  away  above  the  ground  without 


TULIP  TREE 


91 


a  branch  as  shown  in  Fig.  73.     The  tree  flowers  in  the  latter 
part  of  May  but  the  cup  that  holds  the  flower  persists 


FIG.  73.— The  Tulip  Tree. 

throughout  the  winter.  The  leaf,  Fig.  75,  has  four  lobes, 
is  nearly  as  broad  as  it  is  long  and  so  notched  at  the  upper 
end  that  it  looks  different  from  any  other  leaf. 


92 


STUDIES  OF  TREES 


FIG.  74. — Bud  of  the 
Tulip  Tree. 


Form  and  size:  The  tulip  tree 
is  one  of  the  largest,  stateliest  and 
tallest  of  our  trees. 

Range:     Eastern  United  States. 

Soil  and  location:  Requires  a 
deep,  moist  soil. 

Enemies :  Comparatively  free 
from  insects  and  disease. 

Value  for  planting:  The  tree  has 
great  value  as  a  specimen  on  the 
lawn  but  is  undesirable  as  a  street 
tree  because  it  requires  considerable 
moisture  and  transplants  with 
difficulty.  It  should  be  planted 
while  young  and  where  it  can 
obtain  plenty  of  light.  It  grows 
rapidly. 

Commercial  value:  The  wood 
is  commercially  known  as  whitewood 
and  yellow  poplar.  It  is  light,  soft, 
not  strong  and  easily  worked.  It 
is  used  in  construction,  for  inte- 
rior finish  of  houses,  woodenware 
and  shingles.  It  has  a  medicinal 
value. 

Other  characters:  The  flower, 
shown  in  Fig.  75,  is  greenish  yel- 
low in  color,  appears  in  May  and 
resembles  a  tulip;  hence  the  name 
tulip  tree.  The  fruit  is  a  cone. 

Other  common  names:  White- 
wood;  yellow  poplar;  poplar  and 
tulip  poplar. 


SWEET  GUM 


93 


SWEET  GUM  (Liyuidambar  styradflud) 

Distinguishing  characters:    The  persistent,  spiny,  long- 
stemmed  round  fruit;    the  corky  growths  on  the  twigs,  the 


FIG,  75,— Leaf  and  Flower  of  the  Tulip  Tree. 


characteristic   star-shaped  leaves    (Fig.   76)   and  the   very 
shiny  greenish  brown  buds  and  the  perfect   symmetry  of 


94 


STUDIES  OF  TREES 


the    tree   are  the  chief   characters  by  which   to   identify 
the  species. 

Form  and  size:    The  sweet  gum  has  a  beautiful  sym- 
metrical shape,  forming  a  true  monopodium. 


r 


FIG.  76.— Leaf  and  Fruit  of  the  Sweet  Gum. 
Note  the  corky  ridges  along  the  twig. 

Range:  From  Connecticut  to  Florida  and  west  to 
Missouri. 

Soil  and  location:  Grows  in  any  good  soil  but  prefers 
low  wet  ground.  It  grows  rapidly  and  needs  plenty  of 
light. 


AMERICAN  LINDEN 

Enemies:  Is  very  often  a  favorite  of 
leaf-eating  caterpillars. 

Value  for  planting:  The  tree  is 
sought  for  the  brilliant  color  of  its  foliage 
in  the  fall,  and  is  suitable  for  planting 
both  on  the  lawn  and  street.  In  grow- 
ing the  tree  for  ornamental  purposes  it 
is  important  that  it  should  be  fre- 
quently transplanted  in  the  nursery  and 
that  [it  be  transported  with  burlap  wrap- 
ping around  its  roots. 

Commercial  value:  The  wood  is 
reddish  brown  in  color,  tends  to  splin- 
ter and  is  inclined  to  warp  in  drying. 
It  is  used  in  cooperage,  veneer  work  and 
for  interior  finish. 

Other  characters:  On  the  smaller 
branches  there  are  irregular  develop- 
ments of  cork  as  shown  in  Fig.  76, 
projecting  in  some  cases  to  half  an  inch 
in  thickness. 

Other  common  names:    Red  gum. 

Comparisons :  The  cork  elm  is  another 
tree  that  possesses  corky  ridges  along  its 
twigs,  but  this  differs  from  the  sweet  gum 
in  wanting  the  spiny  fruit  and  its  other 
distinctive  traits. 

AMERICAN  LINDEN   (Tilia  Americana) 

Distinguishing  characters:  The  great 
distinguishing  feature  of  any  linden  is 
the  one-sided  character  of  its  bud  and 


FIG.  77.— Bud  of 
the  Linden  Tree, 


96 


STUDIES  OF  TREES 


leaf.  The  bud,  dark  red  and  conical,  carries  a  sort 
of  protuberance  which  makes  it  extremely  one  sided  as 
shown  in  Fig.  77.  The  leaf,  Fig.  78,  is  heart-shaped  with 
the  side  nearest  the  branch  largest. 


FIG.  78. — Leaves  and  Flowers  of  the  European  Linden. 


Form  and  size:  The  American  Linden  is  a  medium- 
sized  tree  with  a  broad  round  head. 

Range:  Eastern  North  America  and  more  common  in 
the  north  than  in  the  south. 

Soil  and  location:     Requires  a  rich,  moist  soil. 


AMEKICAN   LINDEN 


97 


FIG,  79. — European  Linden  Tree. 


STUDIES   OF  TREES 

• 

Enemies:  Its  leaves  are  a 
favorite  food  of  caterpillars 
and  its  wood  is  frequently 
attacked  by  a  boring  insect 
known  as  the  linden  borer  (Sa- 
perda  vestitd). 

Value  for  planting:  The  lin- 
den is  easily  transplanted  and 
grows  rapidly.  It  is  used  for 
lawn  and  street  planting  but  is 
less  desirable  for  these  purposes 
than  'the  European  species. 

Commercial  value :  The  wood 
is  light  and  soft  and  used  for  paper 
pulp,  woodenware,  cooperage  and 
furniture.  The  tree  is  a  favorite 
with  bee  keepers  on  account  of 
the  large  quantities  of  nectar 
contained  in  its  flowers. 

Other  characters:  The  fruit 
is  like  a  pea,  gray  and  woody. 
The  flowers  appear  in  early  July, 
are  greenish-yellow  and  very  fra- 
grant. 

Other  common  names:  Bass- 
wood;  lime-tree;  whitewood. 

Comparisons:  The  European 
lindens,  Fig.  79,  of  which  there 
are  several  species  under  cultiva- 
t  i  o  n  ,  differ  from  the  native 
species  in  having  buds  and  leaves 
smaller  in  size,  more  numerous 
and  darker  in  color. 


FIG.  80.— Bud  of  the 
Umbrella  Tree. 


CUCUMBER  TREE 


99 


THE   MAGNOLIAS 

The  various  species  of 
magnolia  trees  are  readily 
distinguished  by  their  buds. 
They  all  prefer  moist,  rich 
soil  and  have  their  princi- 
pal value  as  decorative  trees 
on  the  lawn.  They  are  dis- 
tinctly southern  trees;  some 
species  under  cultivation  in 
the  United  States  come  from 
Asia,  but  the  two  most 
commonly  grown  in  the 
Eastern  States  are  the  cu- 
cumber tree  and  the  um- 
brella tree. 


CUCUMBER  TREE  (Mag- 
nolia acuminata) 

Distinguishing  charac- 
ters :  The  buds  are  small  and 
slender  compared  with  those 
of  the  other  magnolia  trees 
and  are  covered  with  small 
silvery  silky  hairs.  The 
habit  of  the  tree  is  to  form 
a  straight  axis  of  great 
height  with  a  symmetrical 

mass  of  branches,  producing  a  perfect  monopodial  crown. 
The  tree  is  sometimes  known  as  mountain  magnolia. 


FIG.  81.— Bark  of  the  Black 
Locust. 


100  STUDIES  OF  TREES 

UMBRELLA  TREE  (Magnolia  tripetala) 

Distinguishing  characters:  The  buds,  Fig.  80,  are 
extremely  long,  often  one  and  a  half  inches,  have  a  purple 
color  and  are  smooth.  The  tree  does  not  grow  to  large 
size  and  produces  an  open  spreading  head.  Its  leaves, 
twelve  to  eighteen  inches  long,  are  larger  than  those  of  the 
other  magnolia  trees.  The  tree  is  sometimes  called  elkwood. 

BLACK  LOCUST  (Robinia  pseudacacia) 

Distinguishing  characters:  The  bark  of  the  trunk  is 
rough  and  deeply  ridged,  as  shown  in  Fig.  81.  The  buds 
are  hardly  noticeable  and  often  bear  small  spines  on  one 
side.  The  leaves  are  small,  delicate  and  fern-like. 

Form  and  size :  The  locust  is  a  medium-sized  tree 
developing  a  slender  straight  trunk  when  grown  alongside 
of  others;  see  Fig.  82. 

Range:    Canada  and  United  States. 

Soil  and  location:  The  locust  will  grow  on  almost 
any  soil  except  a  wet,  heavy  one.  It  requires  plenty  of 
light. 

Enemies:  The  locust  borer  has  done  serious  damage  to 
this  tree.  The  grubs  of  this  insect  burrow  in  the  sapwood 
and  kill  the  tree  or  make  it  unfit  for  commercial  use.  The 
locust  miner  is  a  beetle  which  is  now  annually  defoliating 
trees  of  this  species  in  large  numbers. 

Value  for  planting:  It  has  little  value  for  ornamental 
planting. 

Commercial  value:  Though  short-lived,  the  locust 
grows  very  rapidly.  It  is  extremely  durable  in  contact 


COMMON  LOCUST 


101 


with  the  soil  and  possesses  great  strength.  It  is  there- 
fore extensively  grown  for  fence-posts  and  railroad  ties. 
Locust  posts  will  last  from  fifteen  to  twenty  years.  The 
wood  is  valuable  for  fuel. 

Other  characters:    The  flowers  are  showy  pea-shaped 


FIG.  82.—  Black  Locust  Trees. 


panicles  appearing  in  May  and  June.     The  fruit  is  a  small 
pod. 

Other  common  names:     Yellow   locust;  common  locust; 
locust. 


102 


STUDIES   OF  TREES 


Comparisons:     The  honey  locust  (Gleditsia    triacanthos) 
can  be   told    from    the    black    locust  by  the    differences 

in  their  bark.  In  the 
honey  locust  the  bark  is 
not  ridged,  has  a  sort 
of  dark  iron-gray  color 
and  is  often  covered 
with  clusters  of  stout, 
sharp-pointed  thorns  as 
in  Fig.  83.  The  fruit  is 
a  large  pod  often  remain- 
ing on  the  tree  through 
the  winter.  This  tree 
has  an  ornamental,  but 
no  commercial  value. 


HARDY  CATALPA 

(Catalpa  spcciosn) 

C  Distinguishing  char- 

Mfc£{  acters:  The  tree  may 
be  told  by  its  fruit, 
which  hang  in  long 
slender  pods  all  winter. 
The  leaf-scars  appear 
on  the  stem  in  whorls 
of  three  and  rarely  op- 
posite each  other. 

Form  and  size:    The  catalpa  has  a  short,  thick    and 
twisted  trunk  with  an  irregular  head. 

Range:    Central  and  eastern  United  States. 


FIG.  83.— Bark  of  the  Honey 
Locust. 


HARDY  CATALPA 


103 


FIG.  84.— Hardy  Catalpa  Trees. 


104 


STUDIES  OF  TREES 


S  o  i  1  a  n  d  location : 
It    grows    naturally    on 
low    bottom-lands    but 
9          will  also  do  well  in  poor, 
A          dry  soils. 

Enemies:  Practically 
free  from  disease  and 
insects. 

M  Value    for    planting: 

The  catalpa  grows  very 
rapidly  and  is  cultivated 
in  parks  for  ornament 
and  in  groves  for  com- 
mercial purposes.  The 
hardy  catalpa  is  pref- 
erable to  the  common 
catalpa  for  planting. 

Commercial  value : 
The  wood  is  extremely 
durable  in  contact  with 
the  soil  and  is  conse- 
quently used  for  posts 
and  railroad  ties. 

Other  characters : 
The  flowers,  which 
appear  in  late  June  and 
early  July,  are  large, 
white  and  very  showy. 

Other     common 
names:    Indian  bean;    western   catalpa. 

Comparisons :  The  white  flowering  dogwood  (Cornus  flor- 
ida)  is  a  small  tree  which  also  has  its  leaves  in  whorls  of  three 
or  sometimes  opposite.  It  can  be  readily  told  from  other 


FIG.  85.— Bark  of  the  Flowering 
Dogwood. 


WHITE  MULBERRY  105 

trees,  however,  by  the  small  square  plates  into  which  the 
outer  bark  on  the  trunk  divides  itself,  see  Fig.  85,  and 
by  the  characteristic  drooping  character  of  its  branches. 
It  is  one  of  the  most  common  plants  in  our  eastern  deciduous 
forests.  It  is  extremely  beautiful  both  in  the  spring  and 
in  the  fall  and  is  frequently  planted  for  ornament.  There 
are  many  varieties  of  dogwood  in  common  use. 

WHITE  MULBERRY  (Morus  alba) 

A  small  tree  recognized  by  its  small  round  reddish  brown 
buds  and  light  brown,  finely  furrowed  (wavy  looking)  bark. 

The  tree,  probably  a  native  of  China,  is  grown  under 
cultivation  in  eastern  Canada  and  United  States.  It  grows 
rapidly  in  moist  soil  and  is  not  fastidious  in  its  light  require- 
ments. Its  chief  value  is  for  screening  and  for  underplanting 
in  woodlands. 

The  red  mulberry  (Morus  rubra)  is  apt  to  be  confused 
with  the  white  mulberry,  but  differs  in  the  following  char- 
acters: The  leaves  of  the  red  mulberry  are  rough  on  the 
upper  side  and  downy  on  the  under  side,  whereas  the  leaves 
of  the  white  mulberry  are  smooth  and  shiny.  The  buds 
in  the  red  are  larger  and  more  shiny  than  those  of  the  white. 

The  Osage  orange  (Toxylon  pomiferum)  is  similar  to  the 
mulberry  in  the  light,  golden  color  of  its  bark,  but  differs 
from  it  in  possessing  conspicuous  spines  along  the  twigs 
and  branches  and  a  more  ridged  bark. 


CHAPTER  IV 
THE  STRUCTURE  AND  REQUIREMENTS  OF  TREES 

To  be  able  fully  to  appreciate  trees,  their  mode  of  life, 
their  enemies  and  their  care,  one  must  know  something  of 
their  structure  and  life  requirements. 

Structure  of  trees:  Among  the  lower  forms  of  plants 
there  is  very  little  distinction  between  the  various  parts — 
no  differentiation  into  root,  stem,  or  crown.  Often  the 
lower  forms  of  animal  and  vegetable  life  are  so  similar 
that  one  cannot  discriminate  between  them.  But  as  we 
ascend  in  the  scale,  the  various  plant  forms  become  more 
and  more  complex  until  we  reach  the  tree,  which  is  the 
largest  and  highest  form  of  all  plants.  The  tree  is  a  living 
organism  composed  of  cells  like  any  other  living  organism. 
It  has  many  parts,  every  one  of  which  has  a  definite  pur- 
pose. The  three  principal  parts  are:  the  stem,  the  crown, 
and  the  root. 

The  stem:  If  we  examine  the  cross-section  of  a  tree, 
Fig.  86,  we  will  notice  that  it  is  made  up  of  numerous 
rings  arranged  in  sections  of  different  color  and  structure. 
The  central  part  is  known  as  the  pith.  Around  the  pith 
comes  a  dark,  close-grained  series  of  rings  known  as  the 
heartwoodj  and  outside  the  heart-wood  comes  a  lighter 
layer,  the  sap-wood.  The  cambium  layer  surrounds  the 
sap-wood  and  the  bark  covers  all.  The  cambium  layer 
is  the  most  important  tissue  of  the  tree  and,  together  with 
part  of  the  sap-wood,  transports  the  water  and  food  of 

106 


STRUCTURE  AND  REQUIREMENTS  OF  TREES     107 

the  tree.  It  is  for  this  reason  that  a  tree  may  be  hollow, 
without  heart  and  sap-wood,  and  still  produce  foliage 
and  fruit. 

The   crown:      The   crown   varies   in   form   in   different 
species  ?nd  is  developed  by  the  growth  of  new  shoots  from 


heart-wood 


pith 


FIG.  86. — The  Cross-Section  of  a  Tree. 


buds.  The  bud  grows  out  to  a  certain  length  and  forms 
the  branch.  Afterwards  it  thickens  only  and  does  not 
increase  in  length.  New  branches  will  then  form  from 
other  buds  on  the  same  branch.  This  explains  in  part  the 
characteristic  branching  of  trees,  Fig.  87. 

The  leaves    are  the    stomach  and  lungs   of  the    tree. 


108 


STUDIES  OF  TREES 


Their  broad  blades  are  a  device  to  catch  the  sunlight 
which  is  needed  in  the  process  of  digesting  the  food  of 
the  tree.  The  leaves  are  arranged  on  the  twigs  in  such 


FIG.  87. — Characteristic  Form  and  Branching  of  Trees. 
The  trees-  in  the  photograph  are  pin  oaks. 

a  way  as  to  catch  the  most  sunlight.  The  leaves  take 
up  the  carbonic  acid  gas  from  the  air,  decompose  it  under 
the  influence  of  light  and  combine  it  with  the  minerals 
and  water  brought  up  by  the  roots  from  the  soil.  The  re- 
sulting chemical  combinations  are  the  sugars  and  starches 


STRUCTURE  AND  REQUIREMENTS  OF  TREES  109 

used,  by  the  cambium  layer  in  building  up  the  body  of 
the  tree.  A  green  pigment,  chlorophyll,  in  the  leaf  is  the 
medium  by  which,  with  the  aid  of  sunlight,  the  sugars 
are  manufactured. 


FIG.  88.— Roots  of  a  Hemlock  Tree  in  their  Search  for  Water. 


The  chlorophyll  gives  the  leaf  its  green  color,  and  this 
explains  why  a  tree  pales  when  it  is  in  a  dying  condition 
or  when  its  life  processes  are  interfered  with.  The  other 
colors  of  the  leaf — the  reds,  browns  and  yellows  of  the 
fall  or  spring — are  due  to  other  pigments.  These  are 


110  STUDIES  OF  TREES 

angular  crystals  of  different  hues,  which  at  certain  times 
of  the  year  become  more  conspicuous  than  at  others,  a 
phenomenon  which  explains  the  variation  in  the  colors 
of  the  leaves  during  the  different  seasons. 

It  is  evident  that  a  tree  is  greatly  dependent  upon  its 
leaves  for  the  manufacture  of  food  and  one  can,  therefore, 
readily  see  why  it  is  important  to  prevent  destruction  of 
the  leaves  by  insects  or  through  over-trimming. 

The  root:  The  root  develops  in  much  the  same  manner 
as  the  crown.  Its  depth  and  spread  will  vary  with  the 
species  but  will  also  depend  somewhat  upon  the  condition 
of  the  soil  around  it.  A  deep  or  a  dry  soil  will  tend  to 
develop  a  deep  root,  while  a  shallow  or  moist  soil  will 
produce  a  shallow  root,  Fig.  88. 

The  numerous  fine  hairs  which  cover  the  roots  serve 
the  purpose  of  taking  up  food  and  water  from  the  soil, 
while  the  heavy  roots  help  to  support  the  tree.  The  root- 
hairs  are  extremely  tender,  are  easily  dried  out  when 
exposed  to  the  sun  and  wind,  and  are  apt  to  become  over- 
heated when  permitted  to  remain  tightly  packed  for  any 
length  of  time.  These  considerations  are  of  practical  im- 
portance in  the  planting  of  trees  and  in  the  application 
of  fertilizers.  It  is  these  fine  rootlets  far  away  from  the 
trunk  of  the  tree  that  have  to  be  fed,  and  all  fertilizers 
must,  therefore,  be  applied  at  points  some  distance  from 
the  trunk  and  not  close  to  it,  where  merely  the  large, 
supporting  roots  are  located.  In  the  cultivation  of  trees 
the  same  principle  holds  true. 

Requirements  of  trees:  Trees  are  dependent  upon 
certain  soil  and  atmospheric  conditions  which  influence 
their  growth  and  development. 

(1)  Influence  of  moisture:  The  form  of  the  tree  and 
its  growth  and  structure  depend  greatly  upon  the  supply 


STRUCTURE  AND  REQUIREMENTS  OF  TREES     111 

of   moisture.     Botanists   have   taken   the   moisture   factor 
as  the   basis   of   classification  and  have   subdivided  trees 


FIG.  89. — Dead  Branches  at  the  Top  Caused  by  Insufficient  Water. 

into  those  that  grow  in  moist  places  (hydrophytes),  those 
that  grow  in  medium  soils  (mesophytes) ,  and  those  that 
grow  in  dry  places  (xerophytes) .  Water  is  taken  up  by  the 


112  STUDIES  OF  TKEES 

roots  of  the  tree  from  the  soil.  The  liquid  absorbed  by  the 
roots  carries  in  solution  the  mineral  salts — the  food  of  the 
tree — and  no  food  can  be  taken  up  unless  it  is  in  solution. 
Much  of  the  water  is  used  by  the  tree  and  an  enormous 
amount  is  given  off  in  the  process  of  evaporation. 

These  facts  will  explain  some  of  the  fundamental  prin- 
ciples in  the  care  of  trees.  To  a  tree  growing  on  a  city 
street  or  on  a  lawn  where  nature  fails  to  supply  the  requisite 
amount  of  water,  the  latter  must  be  supplied  artificially, 
especially  during  the  hot  summer  months,  or  else  dead 
branches  may  result  as  seen  in  Fig.  89.  Too  much  thinning 
out  of  the  crown  causes  excessive  evaporation,  and  too  much 
cutting  out  in  woodlands  causes  the  soil  to  dry  and  the  trees 
to  suffer  for  the  want  of  moisture.  This  also  explains  why 
it  is  essential,  in  wooded  areas,  to  retain  on  the  ground 
the  fallen  .leaves.  In  decomposing  and  mixing  with  the 
soil,  the  fallen  leaves  not  only  supply  the  trees  with  food 
material,  but  also  tend  to  conserve  moisture  in  the  ground 
and  to  prevent  the  drying  out  cf  the  soil.  Raking  off  the 
leaves  from  wooded  areas,  a  practice  common  in  parks 
and  on  private  estates — hurts  the  trees  seriously.  Some 
soils  may  have  plenty  of  moisture,  but  may  also  be  so 
heavily  saturated  with  acids  or  salts  that  the  tree  cannot 
utilize  the  moisture,  and  it  suffers  from  drought  just  the 
same  as  if  there  had  been  no  moisture  at  all  in  the  soil. 
Such  soils  are  said  to  be  "  physiologically  dry  "  and  need 
treatment. 

In  the  development  of  disease,  moisture  is  a  contrib- 
uting factor  and,  therefore,  in  cavities  or  underneath  band- 
ages where  there  is  likely  to  be  an  accumulation  of  moisture, 
decay  will  do  more  damage  than  in  places  that  are  dry 
and  exposed  to  the  sun. 

(2)  Influence  of  soil:     Soil  is  made  up  of  fine  particles 


STRUCTURE  AND  REQUIREMENTS  OF  TREES     113 

of  sand  and  rock  and  of  vegetable  matter  called  humus. 
A  tree  will  require  a  certain  soil,  and  unsuitable  soils  can 


FIG.  90. — A  Tree  in  the  Open.  Note  the  full  development  of  the  wide 
crown  with  branches  starting  near  the  ground.  The  tree  is  the 
European  larch. 

be  very  often  modified  to  suit  the  needs  of  the  tree.     A 
-deep,   moderately   loose,    sandy   loam,    however,    which   is 


114  STUDIES  OF  TREES 

sufficiently  aerated  and  well  supplied  with  water,  will 
support  almost  any  tree.  Too  much  of  any  one  con- 
stituent will  make  a  soil  unfit  for  the  production  of 
trees.  If  too  much  clay  is  present  the  soil  becomes 
"  stiff."  If  too  much  vegetable  matter  is  present,  the 
soil  becomes  "  sour."  The  physical  character  of  the  soil 
is  also  important.  By  physical  character  is  meant  the 
porosity  which  results  from  breaking  up  the  soil.  This 
is  accomplished  by  ploughing  or  cultivation.  In  nature, 
worms  help  to  do  this  for  the  soil,  but  on  streets  an 
occasional  digging  up  of  the  soil  about  the  base  of  the  tree 
is  essential. 

Humus  or  the  organic  matter  in  the  soil  is  composed  of 
litter,  leaves  and  animal  ingredients  that  have  decayed 
under  the  influence  of  bacteria.  The  more  vegetable 
matter  in  the  humus,  the  darker  the  soil;  and  therefore  a 
good  soil  such  as  one  finds  on  the  upper  surface  of  a  well- 
tilled  farm  has  quite  a  dark  color.  When,  however,  a  soil 
contains  an  unusual  quantity  of  humus,  it  is  known  as 
"  muck,"  and  when  there  is  still  more  humus  present  we 
find  peat.  Neither  of  these  two  soils  is  suitable  for  proper 
tree  growth. 

(3)  Influence  of  light:  Light  is  required  by  the  leaves 
in  the  process  of  assimilation.  Cutting  off  some  of  the  light 
from  a  tree  affects  its  form.  This  is  why  trees  grown  in 
the  open  have  wide-spreading  crowns  with  branches  starting 
near  the  ground  as  in  Fig.  90,  while  the  same  species 
growing  in  the  forest  produces  tall,  lanky  trees,  free  from 
branches  to  but  a  few  feet  from  the  top  as  in  Fig.  91.  Some 
trees  can  endure  more  shade  than  others,  but  all  will  grow 
in  full  light.  This  explains  why  trees  like  the  beech,  hem- 
lock, sugar  maple,  spruce,  holly  and  dogwood  can  grow 
in  the  shade,  while  the  poplar,  birch  and  willow  require 


STRUCTURE  AND  REQUIREMENTS  OF  TREES     115 


git — &  Tree  in  The   Forest.      Note  the  tall  stem  free  from 
branches  and  the  small,  narrow  crown. 


116  STUDIES  OF  TREES 

light.  It  also  explains  why,  in  the  forest,  the  lower  branches 
die  and  fall  off — a  process  known  in  Forestry  as  "  natural 
pruning."  The  influence  of  light  on  the  form  of  trees 
should  be  well  understood  by  all  those  who  plant  trees 
and  by  those  designing  landscape  effects. 

(4)  Influence  of  heat:  Trees  require  a  certain  amount 
of  heat.  They  receive  it  partly  from  the  sun  and  partly 
from  the  soil.  Evaporation  prevents  the  overheating  of 
the  crown.  The  main  stem  of  the  tree  is  heated  by  water 
from  the  soil;  therefore  trees  in  the  open  begin  growth 
in  the  spring  earlier  than  trees  in  the  forest  because  the 
soil  in  the  open  is  warmer.  Shrubs  begin  their  growth 
earlier  than  trees  because  of  the  nearness  of  their  crowns 
to  their  root  systems.  This  also  explains  why  a  warm 
rain  will  start  vegetation  quickly.  Too  much  heat  will 
naturally  cause  excessive  drying  of  the  roots  or  excessive 
evaporation  from  the  leaves  and  therefore  more  water 
is  needed  by  the  tree  in  summer  than  in  winter. 

(5) ' Influence  of  season  and  frost:  The  life  processes  of 
a  tree  are  checked  when  the  temperature  sinks  below  a 
certain  point.  The  tree  is  thus,  during  the  winter,  in  a 
period  of  rest  and  only  a  few  chemical  changes  take  place 
which  lead  up  to  the  starting  of  vegetation.  In  eastern 
United  States,  growth  starts  in  April  and  ceases  during  the 
latter  part  of  August  or  in  early  September.  The  different 
parts  of  a  tree  may  freeze  solid  during  the  winter  without 
injury,  provided  the  tree  is  a  native  one.  Exotic  trees 
may  suffer  greatly  from  extreme  cold.  This  is  one  of  the 
main  reasons  why  it  is  always  advisable  to  plant  native 
trees  rather  than  those  that  are  imported  and  have  not 
yet  been  acclimatized.  Frosts  during  mid-winter  are  not 
quite  as  injurious  as  early  and  late  frosts  and,  therefore, 
if  one  is  going  to  protect  plants  from  the  winter's  cold, 


STRUCTURE  AND  REQUIREMENTS  OF  TREES     117 

it  is  well  to  apply  the  covering  early  enough  and  to  keep 
it  on  late  enough  to  overcome  this  difficulty. 

The  mechanical  injuries  from  frost  are  also  important. 
Snow  and  sleet  will  weigh  down  branches  but  rarely  break 
them,  while  frost  will  cause  them  to  become  brittle  and  to 
break  easily.  Those  who  climb  and  prune  trees  should 
be  especially  cautious  on  frosty  days. 

(6)  Influence  of  air:  On  the  under  side  of  leaves  and 
on  other  surfaces  of  a  tree  little  pores  known  as  stomata 
may  be  found.  In  the  bark  of  birch  and  cherry  trees  these 
openings  are  very  conspicuous  and  are  there  known  as 
lenticels.  These  pores  are  necessary  for  the  breathing 
of  the  tree  (respiration),  whereby  carbonic  acid  gas  is 
taken  in  from  the  air  and  oxygen  given  out.  The  process 
of  assimilation  depends  upon  this  breathing  process  and  it 
is  therefore  evident  that  when  the  stomata  are  clogged 
as  may  occur  where  a  tree  is  subjected  to  smoke  or  dust, 
the  life  processes  of  the  tree  will  be  interfered  with.  The 
same  injurious  effect  results  when  the  stomata  of  the  roots 
are  interfered  with.  Such  interference  may  occur  in  cases 
where  a  heavy  layer  of  soil  is  piled  around  the  base  of  a 
tree,  where  the  soil  about  the  base  of  a  tree  is  allowed  to 
become  compact,  where  a  tree  is  planted  too  deep,  or  where 
the  roots  are  submerged  under  water  for  any  length  of 
time.  In  any  case  the  air  cannot  get  to  the  roots  and  the 
tree  suffers.  Nature  takes  special  cognizance  of  this 
important  requirement  in  the  case  of  cypress  trees,  which 
habitually  grow  under  water.  Here  the  trees  are  provided 
with  special  woody  protuberances  known  as  "  cypress 
knees,"  which  emerge  above  water  and  take  the  necessary 
air.  See  Fig.  18. 

Conclusions:  From  the  foregoing  it  will  be  seen  that 
trees  have  certain  needs  that  nature  or  man  must  supply. 


118  STUDIES  OF  TREES 

These  requirements  differ  with  the  different  species,  and  in 
all  work  of  planting  and  care  as  well  as  in  the  natural 
distribution  of  trees  it  is  both  interesting  and  necessary 
to  observe  these  individual  wants,  to  select  species  in 
accordance  with  local  conditions  and  to  care  for  trees  in 
conformity  with  their  natural  needs. 


CHAPTER  V 
WHAT  TREES  TO  PLANT  AND  HOW 

THE  following  classification  will  show  the  value  of  the 
more  important  trees  for  different  kinds  of  planting.  The 
species  are  arranged  in  the  order  of  their  merit  for  the 
particular  object  under  consideration  and  the  comments 
accompanying  each  tree  are  intended  to  bring  out  its  special 
qualifications  for  that  purpose. 

Conditions  for  tree  growth  in  one  part  of  the  country 
differ  from  those  of  another  and  these  lists,  especially 
applicable  to  the  Eastern  States,  may  not  at  all  fit  some 
other  locality. 

TREES   BEST  FOR  THE   LAWN 

DECIDUOUS 

1.  American  elm  One  of  the  noblest  of  trees. 
(Ulmus  americana)                    Possesses    a    majestic,    wide- 
spreading,    umbrella-shaped 
crown;  is  easily  transplanted, 
and  is  suited  to  a  variety  of 
soils. 

2.  Pin  oak  Has  a  symmetrical  crown 
(Quercus  palustris)                    with   low-drooping   branches; 

requires  a  moist  situation. 

3.  European  linden  Possesses  a  beautiful  shade- 
(Tilia  microphylla)                  bearing  crown;  grows  well  in 

ordinary  soil. 

119 


120 


STUDIES  OF  TREES 


4.  Red  maple 

(Acer  rubrum) 


6.  Copper  beech 

(Fagus  sylvatica,  atropurpurea) 


6.  Coffee  tree 

(Gymnocladus  dioicus) 


7.  European  white  birch 
(Belula  alba) 


8.  Gingko  or  Maiden-hair  tree 
(Gingko  biloba) 


9.  Horsechestnut 

(Aesculus  hippocastanum) 


Shows  pleasing  colors  at  all 
seasons;  grows  best  in  a  fairly 
rich,  moist  soil. 

Exceedingly  beautiful  in 
form,  bark,  and  foliage  and 
possesses  great  longevity  and 
sturdiness.  It  is  difficult  to 
transplant  and  therefore  only 
small  trees  from  6  to  10  feet 
in  height  should  be  used. 

A  unique  and  interesting 
effect  is  produced  by  its 
coarse  branching  and  leaves. 
It  is  free  from  insects  and  dis- 
ease; requires  plenty  of  light; 
will  grow  in  poor  soils. 

A  graceful  tree  and  very 
effective  as  a  single  specimen 
on  the  lawn,  or  in  a  group 
among  evergreens;  should  be 
planted  in  early  spring,  and 
special  care  taken  to  protect 
its  tender  rootlets. 

Where  there  is  plenty  of 
room  for  the  spread  of  its  odd 
branches,  the  gingko  makes  a 
picturesque  specimen  tree.  It 
is  hardy  and  free  from  insect 
pests  and  disease. 

Carries  beautiful,  showy 
flowers,  and  has  a  compact, 
symmetrical  low-branched 
crown;  is  frequently  subject 


WHAT  TKEES  TO  PLANT  AND  HOW 


121 


to  insects  and  disease.     The 

red    flowering  horsechestnut 

(A.   rubicundd)  is      equally 
attractive. 


FIG.  92. — A  Lawn  Tree.     European  Weeping  Beech. 


10.  Sugar  maple 

(Acer  saccharum) 


11.  Soulange's  magnolia 

(Magnolia  soulangeana) 


Has  a  symmetrical  crown 
and  colors  beautifully  in  the 
fall;  requires  a  rich  soil  and 
considerable  moisture. 

Extremely  hardy  and  flow- 
ers in  early  spring  before  the 
leaves  appear. 


122 


STUDIES  OF  TREES 


12.  Flowering  dogwood 

(Cornus  florida) 


13.  Japanese  maple 

(Acer  polymorphum) 


CONIFEROUS 

14.  Oriental  spruce 

(Picea  orienlalis) 


15.  Austrian  pine 

(Pinus  austriaca) 


16.  Ehotan  pine 
(Pinus  excelsd) 


17.  White  pine 

(Pinus  strobus) 


18.  European  larch 

(Larix  europaea) 


Popular  for  its  beautiful 
white  flowers  in  the  early 
spring  and  the  rich  coloring 
of  its  leaves  in  the  fall;  does 
not  grow  to  large  size.  The 
red-flowering  variety  of  this 
tree,  though  sometimes  not 
quite  as  hardy,  is  extremely 
beautiful. 

It  has  several  varieties  of 
different  hues  and  it  colors 
beautifully  in  the  fall;  it  does 
not  grow  to  large  size. 


Forms  a  dignified,  large 
tree  with  a  compact  crown 
and  low  branches;  is  hardy. 

Is  very  hardy;  possesses  a 
compact  crown;  will  grow  in 
soils  of  medium  quality. 

Grows  luxuriantly;  is  digni- 
fied and  beautiful;  requires  a 
good  soil,  and  in  youth  needs 
some  protection  from  extreme 
cold. 

Branches  gracefully  and 
forms  a  large,  dignified  tree; 
will  thrive  on  a  variety  of 
soils. 

Has  a  beautiful  appearance; 
thrives  best  in  moist  situa.* 
tions. 


WHAT  TREES  TO  PLANT  AND    HOW  123 

19.  Blue  spruce  Extremely  hardy;  forms  a 
(Picea  pungens)                       perfect    specimen    plant    for 

the  lawn. 

20.  Japanese  umbrella  pine  Very  hardy;  retains  a  com- 
(Sciadopitys  vcrlicillata)              pact     crown>        An     excellent 

specimen  plant  when  grouped 
with  other  evergreens  on  the 
lawn.  Does  not  grow  to  large 
size. 

21.  Mugho  pine  A    low-growing    evergreen; 
(Pinus  mughus)                       hardy;    important    in    group 

planting. 

22.  Obtuse  leaf  Japanese  cypress       Beautiful  evergreen  of  small 
(Retinospora  obtusa)  sjze .  hardy ;  desirable  for  group 

planting. 

23.  English  yew  An      excellent       evergreen 
(Taxus  baccata}                        usually  of  low  form;  suitable 

for  the  lawn,  massed  with 
others  or  as  a  specimen  plant; 
will  grow  in  the  shade  of  other 
trees.  There  are  various 
forms  of  this  species  of  dis- 
tinctive value, 

TREES  BEST  FOR  THE  STREET 

1.  Oriental  sycamore  Very  hardy;  will  adapt  itself 
(Platanus  orientalis)                   to  city  conditions ;  grows  fairly 

fast  and  is  highly  resistant 
to  insects  and  disease. 

2.  Norway  maple  Very    hardy;    possesses    a 
(Acer  platanoides)                    straight  trunk  and  symmetri- 
cal  crown;   is   comparatively 


124 


STUDIES  OF  TREES 


3.  Red  oak 

(Quercus  rubra) 


free  from  insects  and  disease 
and  will  withstand  the  aver^ 
age  city  conditions. 

Fastest  growing  of  the  oaks; 
very  durable  and  highly  resist- 
ant to  insects  and  disease; 


FIG.  93.— Street  Trees.     Norway  Maples. 


4.  Gingko 

(Gingko  biloba) 


will  grow  in  the  average  soil 
of  the  city  street. 

Hardy  and  absolutely  free 
from  insects  and  disease; 
suited  for  narrow  streets,  and 
will  permit  of  close  planting. 


WHAT  TREES  TO  PLANT  AND  HOW 


125 


6.  European  linden 

(Tilia  microphylla) 


6.  American  elm 

(Ulmus  americana) 


7.  Pin  oak 

(Quercus  palustris) 


8.  Red  maple 

(Acer  rubrum) 


Beautiful  shade-bearing 
crown;  is  very  responsive  to 
good  soil  and  plenty  of  moist- 
ure. 

When  planted  in  rows  along 
an  avenue,  it  forms  a  tall 
majestic  archway  of  great 
beauty.  It  is  best  suited  for 
wide  streets  and  should  be 
planted  further  apart  than  the 
other  trees  listed  above.  Re- 
quires a  fairly  good  soil  and 
plenty  of  moisture,  and  is 
therefore  not  suited  for  plant- 
ing in  the  heart  of  a  large 
city. 

This  tree  exhibits  its  great- 
est beauty  when  its  branches 
are  allowed  to  droop  fairly 
low.  It,  moreover,  needs 
plenty  of  moisture  to  thrive 
and  the  tree  is  therefore  best 
suited  for  streets  in  suburban 
sections,  where  these  condi- 
tions can  be  more  readily  met. 

Beautiful  in  all  seasons  of 
the  year;  requires  a  rich  soil 
and  considerable  moisture. 


126 


STUDIES  OF  TREES 


TREES   BEST   FOR   WOODLAND 


FOR  OPEN  PLACES 

1.  Red  oak 

(Quercus  rubra) 

2.  White  pine 

(Pinus  strobus) 


3.  Red  pine 

(Pinus  resinosa) 

4.  Tulip  tree 

(Liriodendron  tulipifera) 


5.  Black  locust 

(Robinia  pseudacacia) 


6.  White  ash 

(Fraxinus  americana) 

7.  American  elm 

(Vlmus  americana) 


8.  European  larch 

(Larix  europaea) 


Grows  rapidly  to  large  size 
and  produces  valuable  wood; 
will  grow  in  poor  soil. 

Rapid  grower;  endures  but 
little  shade;  wood  valuable; 
will  do  well  on  large  range  of 
soils. 

Very  hardy;  fairly  rapid 
growing  tree. 

Grows  rapidly  into  a  stately 
forest  tree  with  a  clear  tall 
trunk;  wood  valuable;  requires 
a  fairly  moist  soil.  Use  a 
small  tree,  plant  in  the  spring, 
and  pay  special  attention  to 
the  protection  of  the  roots  in 
planting. 

Grows  rapidly;  adapts  itself 
to  poor,  sandy  soils.  The 
wood  is  suitable  for  posts  and 
ties. 

Grows  rapidly;  prefers  moist 
situations.  Wood  valuable. 

Grows  rapidly  to  great 
height;  will  not  endure  too 
much  shade;  does  best  in  a 
deep  fertile  soil.  Wood  valu- 
able. 

Grows  rapidly;  prefers  moist 
situations. 


WHAT  TKEES  TO  PLANT  AND   HOW  127 


FIG.  94,— Woodland  Trees,    Red  Oaks, 


128 


STUDIES  OF  TREES 


FOR  PLANTING  UNDER  THE 
SHADE  OF  OTHER  TREES 

9.  Beech  (Fagus) 


10.  Hemlock 

(Tsuga  canadensis) 

11.  Dogwood 

(Cornus  florida) 


12.  Blue  beech 

(Carpinus  caroliniand) 


Will  stand  heavy  shade; 
holds  the  soil  well  along  banks 
and  steep  slopes.  Both  the 
American  and  the  English 
species  are  desirable. 

Will  stand  heavy  shade 
and  look  effective  in  winter 
as  well  as  in  summer. 

Will  grow  under  other  trees; 
flowers  beautifully  in  the 
spring  and  colors  richly  in  the 
fall. 

Native  to  the  woodlands 
of  the  Eastern  States;  looks 
well  in  spring  and  fall. 


TREES  BEST   FOR   SCREENING 


1.  Hemlock 

(Tsuga  canadensis) 


2.  Osage  orange 

(Toxylon  pomiferum) 

3.  English  hawthorn 
(Cratagus  oxyacantha) 

4.  Lombardy  poplar 
(Populus  nigra  var.  italica) 


Will  stand  shearing  and 
will  screen  in  winter  as  well 
as  in  summer.  Plant  from 
2  to  4  feet  apart  to  form  a 
hedge. 

Very   hardy.     Plant    close. 

Flowers  beautifully  and 
grows  in  compact  masses. 
Plant  close. 

Forms  a  tall  screen  and 
grows  under  the  most  unfavor- 
able conditions.  Plant  8  to 
12  feet  apart. 


WHAT  TREES  TO  PLANT   AND  HOW  129 

Quality  of  trees:  Trees  grown  in  a  nursery  are 
preferable  for  transplanting  to  trees  grown  in  the  forest. 
Nursery-grown  trees  possess  a  well-developed  root  system 
with  numerous  fibrous  rootlets,  a  straight  stem,  a  sym- 
metrical crown,  and  a  well-defined  leader.  Trees  grown  in 
neighboring  nurseries  are  preferable  to  those  grown  at 
great  distances,  because  they  will  be  better  adapted  to  local 
climatic  and  soil  conditions.  The  short  distances  over 
which  they  must  be  transported  also  will  entail  less  danger 
to  the  roots  through  drying.  For  lawn  planting,  the 
branches  should  reach  low  to  the  ground,  while  for  street 
purposes  the  branches  should  start  at  about  seven  feet 
from  the  ground.  For  street  planting,  it  is  also  important 
that  the  stem  should  be  perfectly  straight  and  about  two 
inches  in  diameter.  For  woodland  planting,  the  form  of 
the  tree  is  of  minor  consideration,  though  it  is  well  to  have 
the  leader  well  defined  here  as  well  as  in  the  other  cases. 
See  Fig.  95. 

When  and  how  to  procure  the  trees:  The  trees  should 
be  selected  in  the  nursery  personally.  Some  persons  prefer 
to  seal  the  more  valuable  specimens  with  leaden  seals.  Fall 
is  the  best  time  to  make  the  selection,  because  at  that  time 
one  can  have  a  wider  choice  of  material.  Selecting  thus 
early  will  also  prevent  delay  in  delivery  at  the  time  when 
it  is  desired  to  plant. 

When  to  plant:  The  best  time  to  plant  trees  is  early 
spring,  just  before  growth  begins,  and  after  the  frost  is 
out  of  the  ground.  From  the  latter  part  of  March  to  the 
early  part  of  May  is  generally  the  planting  period  in  the 
Eastern  States. 

Where  one  has  to  plant  both  coniferous  and  deciduous 
trees,  it  is  best  to  get  the  deciduous  in  first,  and  then  the 
conifers. 


130  STUDIES  OF  TREES 

How  to  plant:  The  location  of  the  trees  with  relation 
to  each  other  should  be  carefully  considered.  On  the  lawn, 
they  should  be  separated  far  enough  to  allow  for  the  full 
spread  of  the  tree.  On  streets,  trees  should  be  planted 
thirty  to  thirty -five  feet  apart  and  in  case  of  the  elm,  forty 
to  fifty  feet.  In  woodlands,  it  is  well  to  plant  as  close  as 
six  feet  apart  where  small  seedlings  are  used  and  about 
twelve  feet  apart  in  the  case  of  trees  an  inch  or  more  in 
diameter.  An  abundance  of  good  soil  (one  to  two  cubic 
yards)  is  essential  with  each  tree  where  the  specimens  used 
are  an  inch  or  two  in  diameter.  A  rich  mellow  loam,  such 
as  one  finds  on  the  surface  of  a  well-tilled  farm,  is  the  ideal 
soil.  Manure  should  never  be  placed  in  direct  contact  with 
the  roots  or  stem  of  the  tree. 

Protection  of  the  roots  from  drying  is  the  chief  pre- 
caution to  be  observed  during  the  planting  process,  and 
for -this  reason  a  cloudy  day  is  preferable  to  a  sunny  day 
for  planting.  In  case  of  evergreens,  the  least  exposure 
of  the  roots  is  liable  to  result  disastrously,  even  more  so 
than  in  case  of  deciduous  trees.  This  is  why  evergreens 
are  lifted  from  the  nursery  with  a  ball  of  soil  around  the 
roots.  All  bruised  roots  should  be  cut  off  before  the  tree 
is  planted,  and  the  crown  of  the  tree  of  the  deciduous 
species  should  be  slightly  trimmed  in  order  to  equalize  the 
loss  of  roots  by  a  corresponding  decrease  in  leaf  surface. 

The  tree  should  be  set  into  the  tree  hole  at  the  same 
depth  that  it  stood  in  the  nursery.  Its  roots,  where  there 
is  no  ball  of  soil  around  them,  should  be  carefully  spread 
out  and  good  soil  should  be  worked  in  carefully  with 
the  fingers  among  the  fine  rootlets.  Every  root  fibre 
is  thus  brought  into  close  contact  with  the  soil.  More 
good  soil  should  be  added  (in  layers)  and  firmly  packed  about 
the  roots.  The  last  layer  should  remain  loose  so  that  it  may 


WHAT  TREES  TO  PLANT  AND  HOW 


131 


FIG.  95. — Specifications  for  a  Street  Tree. 


132 


STUDIES  OF  TREES 


act  as  a  mulch  or  as  an  absorbent  of  moisture.    The  tree 
should  then  be  thoroughly  watered. 

After  care:  During  the  first  season  the  tree  should  be 
watered  and  the  soil  around  its  base  slightly  loosened  at 
least  once  a  week,  especially  on  hot  summer  days.  Where 


FIG.  96. — A  Home  Nursery.     (Austrian  pines  in  front.) 

trees  are  planted  on  streets,  near  the  curb,  they  should  also 
be  fastened  to  stakes  and  protected  with  a  wire  guard 
six  feet  high.  See  Fig.  95.  Wire  netting  of  ^-inch  mesh 
and  17  gauge  is  the  most  desirable  material. 

Suggestions  for  a  home  or  school  nursery:  Schools, 
farms,  and  private  estates  may  conveniently  start  a  tree 
nursery  on  the  premises  and  raise  their  own  trees.  Two- 


WHAT  TREES  TO  PLANT  AND  HOW  133 

year  seedling  trees  or  four-year  transplants  are  best  suited 
for  this  purpose.  These  may  be  obtained  from  several 
reliable  nurseries  in  various  parts  of  the  country  that  make 
a  specialty  of  raising  small  trees  for  such  purposes.  The 
cost  of  such  trees  should  be  from  three  to  fifteen  dollars 
per  thousand. 

The  little  trees,  which  range  from  one  to  two  feet  in 
height,  will  be  shipped  in  bundles.  Immediately  upon 
arrival,  the  bundles  should  be  untied  and  the  trees  immersed 
in  a  pail  containing  water  mixed  with  soil.  The  bundles 
should  then  be  placed  in  the  ground  temporarily,  until 
they  can  be  set  out  in  their  proper  places.  In  this  process, 
the  individual  bundles  should  be  slanted  with  their  tops 
toward  the  south,  and  the  spot  chosen  should  be  cool  and 
shady.  At  no  time  should  the  roots  of  these  plants  be 
exposed,  even  for  a  moment,  to  sun  and  wind,  and  they 
should  always  be  kept  moist.  The  little  trees  may  remain  in 
this  trench  for  two  weeks  without  injury.  They  should 
then  be  planted  out  in  rows,  each  row  one  foot  apart  for 
conifers  and  two  feet  for  broadleaf  trees.  The  individual 
trees  should  be  set  ten  inches  apart  in  the  row.  Careful 
weeding  and  watering  is  the  necessary  attention  later  on. 


CHAPTER  VI 
THE  CARE  OF  TREES 

STUDY  I.     INSECTS  INJURIOUS  TO  TREES  AND  HOW 
TO    COMBAT   THEM 

IN  a  general  way,  trees  are  attacked  by  three  classes  of 
insects,  and  the  remedy  to  be  employed  in  each  case 
depends  upon  the  class  to  which  the  insect  belongs.  The 
three  classes  of  insects  are: 

1.  Those  that  chew  and   swallow  some  portion  of  the 
leaf;    as,  for  example,  the  elm  leaf  beetle,  and  the  tussock, 
gipsy,  and  brown-tail  moths. 

2.  Those  that  suck  the  plant  juices  from  the  leaf  or 
bark;    such   as  the    San  Jose  scale,  oyster-shell,  and  scurfy 
scales,  the  cottony  maple  scale,  the  maple  phenacoccus  on 
the  sugar  maples,  and  the  various  aphides  on  beech,  Nor- 
way maple,  etc. 

3.  Those  that  bore  inside  of  the  wood  or  inner  bark. 
The  principal  members  of  this  class  are  the   leopard  moth, 
the  hickory-bark    borer,  the    sugar-maple   borer,  the   elm 
borer,  and  the  bronze-birch  borer. 

The  chewing  insects  are  destroyed  by  spraying  the  leaves 
with  arsenate  of  lead  or  Paris  green.  The  insects  feed  upon 
the  poisoned  foliage  and  thus  are  themselves  poisoned. 

The  sucking  insects  are  killed  by  a  contact  poison:  that 
is,  by  spraying  or  washing  the  affected  parts  of  the  tree 
with  a  solution  which  acts  externally  on  the  bodies  of  the 

134 


INSECTS  INJURIOUS  TO  TREES 


135 


insects,  smothering  or  stifling  them.  The  standard  solu- 
tions for  this  purpose  are  kerosene  emulsion,  soap  and  water, 
tobacco  extract,  or  lime-sulfur  wash. 


. 


FIG.  97. — A  Gas-power  Spraying  Apparatus. 


The  boring  insects  are  eliminated  by  cutting  out  the 
insect  with  a  knife,  by  injecting  carbon  bisulphide  into 
the  burrow  and  clogging  the  orifice  immediately  after 
injection  with  putty  or  soap,  or  in  some  cases  where  the 


136 


STUDIES  OF  TREES 


tree  is  hopelessly  infested,  by  cutting  down  and  burning  the 
entire  tree. 


FIG.  98.— A  Barrel  Hand-pump  Spraying  Outfit. 

For    information    regarding    the    one    of     these    three 
classes  to  which  any  particular  insect  belongs,   and  for 


INSECTS  INJURIOUS  TO  TREES 


137 


specific  instructions  on  the  application  of  a  remedy,  the  reader 
is  advised  to  write  to  his  State  Entomologist  or  to  the 
U.  S.  Bureau  of  Entomol- 
ogy at  Washington,  D.  C. 
The  letter  should  state  the 
name  of  the  tree  affected, 
together  with  the  character 
of  the  injury,  and  should 
be  accompanied  by  a  spec- 
imen of  the  insect,  or  by 
a  piece  of  the  affected  leaf 
or  bark,  preferably  by 
both.  The  advice  received 
will  be  authentic  and  will 
be  given  without  charge. 

When  to  spray:  In  the 
cose  of  chewing  insects,  the 
latter  part  of  May  is  the 
time  to  spray.  The  cater- 
pillars hatch  from  their 
eggs,  and  the  elm  leaf 
beetle  leaves  its  winter 
quarters  at  that  time.  In 
the  case  of  sucking  insects, 
the  instructions  will  have 
to  be  more  specific,  de- 
pending upon  the  partic- 
ular insect  in  question. 
Some  sucking  insects  can 
best  be  handled  in  May  or 

early  June  when  their  young  emerge,  others  can  be 
effectively  treated  in  the  fall  or  winter  when  the  trees 
are  dormant. 


FIG.  99. — Egg-masses  of  the 
Tussock  Moth. 


138  STUDIES  OF  TREES 

How  to  spray:  Thoroughness  is  the  essential  principle 
in  all  spraying.  In  the  case  of  leaf-eating  insects,  this 
means  covering  every  leaf  with  the  poison  and  applying 
it  to  the  under  side  of  the  leaves,  where  the  insects  generally 
feed.  In  the  case  of  sucking  insects,  thoroughness  means 
an  effort  to  touch  every  insect  with  the  spray.  It  should 
be  borne  in  mind  that  the  insect  can  be  killed  only 
when  hit  with  the  chemical.  The  solution  should  be 
well  stirred,  and  should  be  applied  by  means  of  a  nozzle 
that  will  coat  every  leaf  with  a  fine,  mist-like  spray. 
Mere  drenching  or  too  prolonged  an  application  will 
cause  the  solution  to  run  off.  Special  precautions  should 
be  taken  with  contact  poisons  to  see  that  the  formula 
is  correct.  Too  strong  a  solution  will  burn  the  foliage 
and  tender  bark. 

Spraying  apparatus:  There  are  various  forms  of  spray- 
ing apparatus  in  the  market,  including  small  knapsack 
pumps,  barrel  hand-pumps,  and  gasolene  and  gas-power 
sprayers,  Figs.  97  and  98.  Hose  and  nozzles  are  essential 
accessories.  One-half  inch,  three-ply  hose  of  the  best 
quality  is  necessary  to  stand  the  heavy  pressure  and  wear. 
Two  50-foot  lengths  is  the  usual  quantity  required  for 
use  with  a  barrel  hand-pump.  Each  line  of  hose  should  be 
supplied  with  a  bamboo  pole  10  feet  long,  having  a  brass 
tube  passed  through  it  to  carry  the  nozzle.  The  Vermorel 
nozzle  is  the  best  type  to  use.  The  cost  of  a  barrel  outfit, 
including  two  lines  of  hose,  nozzles  and  truck,  should  be 
from  $30  to  $40.  Power  sprayers  cost  from  $150  to  $300 
or  more. 

Spraying  material:  Ar senate  of  lead  should  be  used  in 
the  proportion  of  4  pounds  of  the  chemical  to  50  gallons 
of  water.  A  brand  of  arsenate  of  lead  containing  at  least 
14  per  cent  of  arsenic  oxid  with  not  more  than  50  per 


INSECTS  INJURIOUS  TO  TREES  139 

cent  of  water  should  be  insisted  upon.  This  spray  may 
be  used  successfully  against  caterpillars  and  other  leaf- 
eating  insects  in  the  spring  or  summer. 

Whale-oil  soap  should  be  used  at  the  rate  of  1|  pounds  of 
the  soap  to  1  gallon  of  hot  water,  if  applied  to  the  tree 
in  winter.  As  a  spray  in  summer,  use  1  pound  of  the 
soap  to  5  gallons  of  water.  This  treatment  is  useful 
for  most  sucking  insects. 

Lime-sulfur  wash  is  an  excellent  material  to  use  against 
sucking  insects,  such  as  the  San  Jose"  scale  and  other  armored 
scales.  The  application  of  a  lime-sulfur  wash  when  put  on 
during  the  dormant  season  is  not  likely  to  harm  a  tree 
and  has  such  an  excellent  cleansing  effect  that  the  benefits 
to  be  derived  in  this  direction  alone  are  often  sufficient  to 
meet  the  cost  of  the  treatment.  Lime-sulfur  wash  consists 
of  a  mixture,  boiled  one  hour,  of  40  pounds  of  lime  and 
80  pounds  of  sulfur,  in  50  gallons  of  water.  It  may  be 
had  in  prepared  form  and  should  then  be  used  at  the  rate 
of  1  gallon  to  about  9  gallons  of  water  in  winter  or  early 
spring  before  the  buds  open.  At  other  times  of  the  year 
and  for  the  softer-bodied  insects  a  more  diluted  mixture, 
possibly  1  part  to  30  or  40  parts  of  water,  should  be  used, 
varying  with  each  case  separately. 

Kerosene  emulsion  consists  of  one-half  pound  of  hard 
soap,  1  gallon  of  boiling  water,  and  2  gallons  of  kerosene. 
It  may  be  obtained  in  prepared  form  and  is  then  to  be  used 
at  the  rate  of  one  part  of  the  solution  to  nine  parts  of  water 
when  applied  in  winter  or  to  the  bark  only  in  summer. 
Use  2  gallons  of  the  solution  to  a  40-gallon  barrel  of  water 
when  applying  it  to  the  leaves  in  the  summer.  Kerosene 
emulsion  is  useful  as  a  treatment  for  scale  insects.  . 

Tobacco  water  should  be  prepared  by  steeping  one-half 
pound  of  tobacco  stems  or  leaves  in  a  gallon  of  boiling  water 


140  STUDIES  OF  TREES 

and  later  diluting  the  product  with  5  to  10  gallons  of  water. 
It  is  particularly  useful  for  plant  lice  in  the  summer. 

The  life  history  of  an  insect:  In  a  general  way,  all 
insects  have  four  stages  of  transformation  before  a  new 
generation  is  produced.  It  is  important  to  consider  the 
nature  of  these  four  stages  in  order  that  the  habits  of  any 
particular  insect  and  the  remedies  applicable  in  combating 
it  may  be  understood. 

All  insects  develop  from  eggs.  Fig.  99.  The  eggs  then 
hatch  into  caterpillars  or  grubs,  which  is  the  larva  stage, 
in  which  most  insects  do  the  greatest  damage  to  trees.  The 
caterpillars  or  grubs  grow  and  develop  rapidly,  and  hence 
their  feeding  is  most  ravenous.  Following  the  larva  stage 
comes  the  third  or  pupa  stage,  which  is  the  dormant  stage 
of  the  insect.  In  this  stage  the  insect  curls  itself  up  under 
the  protection  of  a  silken  cocoon  like  the  tussock  moth, 
or  of  a  curled  leaf  like  the  brown-tail  moth,  or  it  may  be 
entirely  unsheltered  like  the  pupa  of  the  elm  leaf  beetle. 
After  the  pupa  stage  comes  the  adult  insect,  which  may  be  a 
moth  or  a  beetle. 

A  study  of  the  four  stages  of  any  particular  insect  is 
known  as  a  study  of  its  life  history.  The  important  facts 
to  know  about  the  life  history  of  an  insect  are  the  stage 
in  which  it  does  most  of  its  feeding,  and  the  period  of  the 
year  in  which  this  occurs.  It  is  also  important  to  know 
how  the  insect  spends  the  winter  in  order  to  decide  upon 
a  winter  treatment. 


INSECTS  INJURIOUS  TO  TREES  141 

IMPORTANT  INSECTS 

THE  ELM  LEAF  BEETLE 

Life  history:  The  elm  leaf  beetle,  Fig.  100,  is  annually 
causing  the  defoliation  of  thousands  of  elm  trees  throughout 
the  United  States.  Several  successive  defoliations  are 
liable  to  kill  a  tree.  The  insects  pass  the  winter  in  the 
beetle  form,  hiding  themselves  in  attics  and  wherever 
else  they  can  secure  shelter.  In  the  middle  of  May  when 
the  buds  of  the  elm  trees  unfold,  the  beetles  emerge  from  their 
winter  quarters,  mate,  and  commence  eating  the  leaves, 
thus  producing  little  holes  through  them.  While  this 
feeding  is  going  on,  the  females  deposit  little,  bright  yellow 
eggs  on  the  under  side  of  the  leaves,  which  soon  hatch  into 
small  larvae  or  grubs.  The  grubs  then  eat  away  the  soft 
portion  of  the  leaf,  causing  it  to  look  like  lacework.  The 
grubs  become  full  grown  in  twenty  days,  crawl  down  to  the 
base  of  the  tree,  and  there  transform  into  naked,  orange- 
colored  pupae.  This  occurs  in  the  early  part  of  August. 
After  remaining  in  the  pupa  stage  about  a  week,  they  change 
into  beetles  again,  which  either  begin  feeding  or  go  to 
winter  quarters. 

Remedies:  There  are  three  ways  of  combating  this 
insect:  First,  by  spraying  the  foliage  with  arsenate  of  lead 
in  the  latter  part  of  May  while  the  beetles  are  feeding, 
and  repeating  the  spraying  in  June  when  the  larvae  emerge. 
The  spraying  method  is  the  one  most  to  be  relied  on  in 
fighting  this  insect.  A  second,  though  less  important 
remedy,  consists  in  destroying  the  pupce  when  they  gather 
in  large  quantities  at  the  base  of  the  tree.  This  may  be 
accomplished  by  gathering  them  bodily  and  destroying  them, 
or  by  pouring  hot  water  or  a  solution  of  kerosene  over  them. 


FIG.  100.— The  Elm  Leaf  Beetle.     (After  Dr.  E.  P.  Felt.) 

1.  Egg  cluster,  enlarged,  la.  Single  egg,  greatly  enlarged.  2.  Young  larva, 
enlarged.  3.  Full  grown  larva,  much  enlarged.  4.  Pupa,  enlarged.  5.  Over- 
wintered beetle,  enlarged.  6.  Fresh,  brightly  colored  beetle,  enlarged.  7.  Under 
surface  of  leaf  showing  larvae  feeding.  8.  Leaf  eaten  by  larva?.  9.  Leaf  showing 
holea  eaten  by  beetles. 

142 


INSECTS  INJURIOUS  TO  TREES  143 

In  large  trees  it  may  be  necessary  to  climb  to  the  crotches 
of  the  main  limbs  to  get  some  of  them.  The  third  remedy 
lies  in  gathering  and  destroying  the  adult  beetles  when  found 
in  their  winter  quarters.  The  application  of  bands  of 
burlap  or  "  tanglefoot/'  or  of  other  substances  often  seen 
on  the  trunks  of  elm  trees  is  useless,  since  these  bands 
only  prevent  the  larva?  from  crawling  down  from  the  leaves 
to  the  base  and  serve  to  prevent  nothing  from  crawling  up. 
Scraping  the  trunks  of  elm  trees  is-  also  a  waste  of  effort. 

THE  TUSSOCK  MOTH 

Life  history:  This  insect  appears  in  the  form  of  a 
red-headed,  yellow-colored  caterpillar  during  the  latter 
part  of  May,  and  in  June  and  July.  The  caterpillars 
surround  themselves  with  silken  cocoons  and  change  into 
pupse.  The  mature  moths  emerge  from  the  cocoons  after 
a  period  of  about  two  weeks,  and  the  females,  which 
are  wingless,  soon  deposit  their  eggs  on  the  bark  of  trees, 
on  twigs,  fences,  and  other  neighboring  objects.  These 
eggs  form  white  clusters  of  nearly  350  individual  eggs  each, 
arid  are  very  conspicuous  all  winter,  see  Fig.  101. 

Remedies:  There  are  two  ways  of  combating  this 
insect:  (1)  By  spraying  with  arsenate  of  lead  for  the  cater- 
pillars during  the  latter  part  of  May  and  early  June. 
(2)  By  removing  and  destroying  the  egg  masses  in  the  fall 
or  winter. 

THE  GIPSY  MOTH 

Life  history:  This  insect,  imported  from  Europe  to 
this  country  in  1868,  has  ever  since  proved  a  serious  enemy 
of  most  shade,  forest,  and  fruit  trees  in  the  New  England 


144 


STUDIES  OF  TREES 


FIG.  101.— The  Tussock  Moth.     (After  Dr.  E.  P.  Felt.) 

1.  Caterpillar.  2.  Male  moth.  3.  Female  moth  laying  eggs.  4  Cocoons. 
5.  Cast  skins  of  caterpillar.  6.  Work  of  young  caterpillar.  7.  Male  pupa. 
8  and  9.  Girdled  branches. 


INSECTS  INJURIOUS  TO  TREES        145 

States.  It  even  feeds  on  evergreens,  killing  the  trees 
by  a  single  defoliation. 

The  insect  appears  in  the  caterpillar  stage  from  April 
to  July.  It  feeds  at  night  and  rests  by  day.  The  mature 
caterpillar,  which  is  dark  in  color,  may  be  recognized  by 
rows  of  blue  and  red  spots  along  its  back.  After  July, 
egg  masses  are  deposited  by  the  female  moths  on  the  bark 
of  trees,  and  on  leaves,  fences,  and  other  neighboring  objects. 
Here  they  remain  over  the  winter  until  they  hatch  in  the 
spring.  The  flat  egg  masses  are  round  or  oval  in  shape, 
and  are  yellowish-brown  in  color.  See  Fig.  102. 

Remedies:  Spray  for  the  caterpillars  in  June  with 
arsenate  of  lead  and  apply  creosote  to  the  egg  masses 
whenever  found. 


THE  BROWN-TAIL  MOTH 

Life  history:  This  insect  was  introduced  here  from 
Europe  in  1890  and  has  since  done  serious  damage  to  shade, 
forest,  and  fruit  trees,  and  to  shrubs  in  the  New  England 
States. 

It  appears  in  the  caterpillar  stage  in  the  early  spring 
and  continues  to  feed  on  the  leaves  and  buds  until  the  last 
of  June.  Then  the  caterpillars  pupate,  the  moths  come  out, 
and  in  July  and  August  the  egg  clusters  appear.  These 
hatch  into  caterpillars  which  form  nests  for  themselves 
by  drawing  the  leaves  together.  Here  they  remain  pro- 
tected until  the  spring.  See  Fig.  103. 

Remedies:  Collect  the  winter  nests  from  October  to 
April  and  burn  them.  Also  spray  the  trees  for  caterpil- 
lars in  early  May  and  especially  in  August  with  arsenate 
of  lead. 


146 


STUDIES  OF  TREES. 


w 


FIG.  102.— The  Gipsy  Moth.   (After  F.  W.  Rane  Mass.  State  Forester.) 


INSECTS  INJUKIOUS  TO  THEES 


147 


j 


FIG.  103.— The  Brown-tail  Moth.     (After  F.  W.  Rane,  Mass.  State 

Forester.) 


148 


STUDIES  OF  TREES 


FIG.  104.— Larva  of  the  Leopard  Moth. 

THE  FALL  WEBWORM 

The  caterpillars  of  this  insect  congregate  in  colonies 
and  surround  themselves  with  a  web  which  often  reaches 
the  size  of  a  foot  or  more  in  diameter.  These  webs  are  com- 
mon on  trees  in  July  and  August.  Cutting  off  the  webs 
or  burning  them  on  the  twigs  is  the  most  practical  remedy. 


INSECTS  INJUKIOUS  TO  TREES 


149 


FIG,  105. — Branch  Showing  Work  of  the  Leopard  Moth  Larva. 

THE  LEOPARD  MOTH 

Life  history:  This  insect  does  its  serious  damage  in 
the  grub  form.  The  grubs  which  are  whitish  in  color 
with  brown  heads,  and  which  vary  in  size  from  f  of  an 
inch  to  3  inches  in  length  (Fig.  104),  may  be  found  boring 
in  the  wood  of  the  branches  and  trunk  of  the  tree  all  winter. 
Fig.  105.  The  leopard  moth  requires  two  years  to  com- 


150  STUDIES  OF  TREES 

plete  its  round  of  life.  The  mature  moths  are  marked  with 
dark  spots  resembling  a  leopard's  skin,  hence  the  name. 
Fig.  106.  It  is  one  of  the  commonest  and  most  destructive 
insects  in  the  East  and  is  responsible  for  the  recent  death 
of  thousands  of  the  famous  elm  trees  in  New  Haven  and 
Boston.  Fig.  107. 

Remedies:     Trees  likely  to  be  infested  with  this  insect 
should  be  examined  three  or  four  times  a  year  for  wilted 


FIG.  106.— The  Leopard  Moth. 

twigs,  dead  branches,  and  strings  of  expelled  frass;  all 
of  which  may  indicate  the  presence  of  this  borer.  Badly 
infested  branches  should  be  cut  off  and  burned.  Trees  so 
badly  infested  that  treatment  becomes  too  complicated 
should  be  cut  down  and  destroyed.  Where  the  insects 
are  few  and  can  be  readily  reached,  an  injection  of  carbon 
bisulphide  into  the  burrow,  the  orifice  of  which  is  then 
immediately  closed  with  soap  or  putty,  will  often  destroy 
the  insects  within. 


INSECTS  INJURIOUS  TO  TREES 


151 


FIG.  107. — Elm  Tree  Attacked  by  the  Leopard  Moth. 


THE  HICKORY  BARK  BORER 

Life  history:  This  insect  is  a  small  brown  or  black 
beetle  in  its  mature  form  and  a  small  legless  white  grub 
in  its  winter  stage.  The  beetles  appear  from  June  to 


152  STUDIES  OF  TREES 

August.  In  July  they  deposit  their  eggs  in  the  outer 
sapwood,  immediately  under  the  bark  of  the  trunk  and  larger 
branches.  The  eggs  soon  hatch  and  the  grubs  feed  on 
the  living  tissue  of  the  tree,  forming  numerous  galleries. 
The  grubs  pass  the  winter  in  a  nearly  full-grown  condition, 
transform  to  pupse  in  May,  and  emerge  as  beetles  in  June. 
Remedies:  The  presence  of  the  insect  can  be  detected 
by  the  small  holes  in  the  bark  of  the  trees  and  the  fine 
sawdust  which  is  ejected  from  these  holes,  when  the  insects 
are  active.  It  is  important  to  emphasize  the  advisability 
of  detecting  the  fine  sawdust  because  that  is  the  best  indi- 
cation of  the  actual  operations  of  the  hickory  bark  borer. 
These  holes,  however,  will  not  be  noticeable  until  the 
insect  has  completed  its  transformation.  In  summer,  the 
infested  trees  show  wilted  leaves  and  many  dead  twigs. 
Holes  in  the  base  of  the  petioles  of  these  leaves  are  also 
signs  of  the  working  of  the  insect.  Since  the  insect  works 
underneath  the  bark,  it  is  inaccessible  for  treatment  and 
all  infested  trees  should  be  cut  down  and  burned,  or  the 
bark  removed  and  the  insects  destroyed.  This  should  be 
done  before  the  beetles  emerge  from  the  tree  in  June. 

PLANT  LICE  OR  APHIDES 

These  often  appear  on  the  under  side  of  the  leaves  of 
the  beech,  Norway  maple,  tulip  tree,  etc.  They  excrete  a 
sweet,  sticky  liquid  called  "  honey-dew,"  and  cause  the 
leaves  to  curl  or  drop.  Spraying  with  whale-oil  soap  solu- 
tion formed  by  adding  one  pound  of  the  soap  to  five 
gallons  of  water  is  the  remedy. 


TREE  DISEASES  153 


STUDY  II.  TREE  DISEASES 

Because  trees  have  wants  analogous  to  those  of  human 
beings,  they  also  have  diseases  similar  to  those  which 
afflict  human  beings.  In  many  cases  these  diseases  act 
like  cancerous  growths  upon  the  human  body;  in  some 
instances  the  ailment  may  be  a  general  failing  due  to  im- 
proper feeding,  and  in  other  cases  it  may  be  due  to  inter- 
ference with  the  life  processes  of  the  tree. 

How  to  tell  an  ailing  tree:  Whatever  the  cause,  an 
ailing  tree  will  manifest  its  ailment  by  one  or  more  symptoms. 

A  change  of  color  in  the  leaves  at  a  time  when  they  should 
be  perfectly  green  indicates  that  the  tree  is  not  growing 
under  normal  conditions,  possibly  because  of  an  insufficiency 
of  moisture  or  light  or  an  overdose  of  foreign  gases  or  salts. 
Withering  of  the  leaves  is  another  sign  of  irregularity  in 
water  supply.  Dead  tops  point  to  some  difficulty  in  the 
soil  conditions  or  to  some  disease  of  the  roots  or  branches. 
Spotted  leaves  and  mushroom-like  growths  or  brackets 
protruding  from  the  bark  as  in  Fig.  108,  are  sure  signs  of 


In  attempting  to  find  out  whether  a  tree  is  healthy  or 
not,  one  would  therefore  do  well  to  consider  whether  the 
conditions  under  which  it  is  growing  are  normal  or  not; 
whether  the  tree  is  suitable  for  the  location;  whether  the 
soil  is  too  dry  or  too  wet;  whether  the  roots  are  deprived 
of  their  necessary  water  and  air  by  an  impenetrable  cover 
of  concrete  or  soil;  whether  the  soil  is  well  drained  and 
free  from  foreign  gases  and  salts;  whether  the  tree  is  receiving 
plenty  of  light  or  is  too  much  exposed;  and  whether  it  is 
free  from  insects  and  fungi. 

If,  after  a  thorough  examination,  it  is  found  that  the 


154 


STUDIES  OF  TREES 


FIG.  108.— A  Bracket  Fungus  (Elfvingia  megalomd)  on  a  Tulip  Tree. 


TREE  DISEASES  155 

ailment  has  gone  too  far,  it  may  not  be  wise  to  try  to  save 
the  tree.  A  timely  removal  of  a  tree  badly  infested  with 
insects  or  fungi  may  often  be  the  best  procedure  and  may 
save  many  neighboring  trees  from  contagious  infection. 
For  this,  however,  no  rules  can  be  laid  down  and  much  will 
depend  on  the  local  conditions  and  the  judgment  and 
knowledge  of  the  person  concerned. 

Fungi  as  factors  of  disease:  The  trees,  the  shrubs  and 
the  flowers  with  which  we  are  familiar  are  rooted  in  the 
ground  and  derive  their  food  both  from  the  soil  and  from 
the  air.  There  is,  however,  another  group  of  plants, — 
the  fungi, — the  roots  of  which  grow  in  trees  and  other  plants 
and  which  obtain  their  food  entirely  from  the  trees  or 
plants  upon  which  they  grow.  The  fungi  cannot  manu- 
facture their  own  food  as  other  plants  do  and  consequently 
absorb  the  food  of  their  host,  eventually  reducing  it  to 
dust.  The  fungi  are  thus  disease-producing  factors  and  the 
source  of  most  of  the  diseases  of  trees. 

When  we  can  see  fungi  growing  on  a  tree  we  may  safely 
assume  that  they  are  already  in  an  advanced  state  of 
development.  We  generally  discover  their  presence  when 
their  fruiting  bodies  appear  on  the  surface  of  the  tree  as 
shown  in  Fig  109.  These  fruiting  bodies  are  the  familiar 
mushrooms,  puffballs,  toadstools  or  shelf-like  brackets 
that  one  often  sees  on  trees.  In  some  cases  they  spread 
over  the  surface  of  the  wood  in  thin  patches.  They  vary 
in  size  from  large  bodies  to  mere  pustules  barely  visible 
to  the  naked  eye.  Their  variation  in  color  is  also  significant, 
ranging  from  colorless  to  black  and  red  but  never  green. 
They  often  emulate  the  color  of  the  bark,  Fig.  110. 

Radiating  from  these  fruiting  bodies  into  the  tissues 
of  the  tree  are  a  large  number  of  minute  fibers,  comprising 
the  mycelium  of  the  fungus.  These  fibers  penetrate  the 


156 


STUDIES  OF  TREES 


body  of  the  tree  in  all  directions  and  absorb  its  food.  The 
mycelium  is  the  most  important  part  of  the  fungous  growth. 
If  the  fruiting  body  is  removed,  another  soon  takes  its 
place,  but  if  the  entire  mycelium  is  cut  out,  the  fungus 


FIG.  109.— The  Fruiting  Body  of  a  Fungus. 

will  never  come  back.  The  fruiting  body  of  the  fungus 
bears  the  seed  or  spores.  These  spores  are  carried  by  the 
wind  or  insects  to  other  trees  where  they  take  root  in  some 
wound  or  crevice  of  the  bark  and  start  a  new  infestation. 
The  infestation  will  be  favored  in  its  growth  if  the  spore 


TREE  DISEASES 


157 


can  find  plenty  of  food,  water,  warmth  and  darkness. 
As  these  conditions  generally  exist  in  wounds  and  cavities 
of  trees,  it  is  wise  to  keep  all  wounds  well  covered  with 


FIG.  110. — The  Birch-fungus  rot.      (Polyporus  betulinus  Fr.)     Note  the 
similarity  in  the  color  of  the  fruiting  body  and  bark  of  the  tree. 

coal  tar  and  to  so  drain  the  cavities  that  moisture  cannot 
lodge  in  them.  This  subject  will  be  gone  into  more  fully 
in  the  following  two  studies  on  "  Pruning  Trees"  and  "  Tree 
Repair." 

While  the  majority  of  the  fungi  grow  on  the  trunks 


158  STUDIES  OF  TREES 

and  limbs  of  trees,  some  attack  the  leaves,  some  the  twigs 
and  others  the  roots.     Some  fungi  grow  on  living  wood 
some  on  dead  wood  and  some  on  both.     Those  that  attack 
the  living  trees  are  the  most  dangerous  from  the  stand- 
point of  disease. 

The  chestnut  disease:  The  disease  which  is  threaten- 
ing the  destruction  of  all  the  chestnut  trees  in  America 
is  a  fungus  which  has,  within  recent  years,  assumed  such 
vast  proportions  that  it  deserves  special  comment.  The 
fungus  is  known  as  Diaporthe  parasitica  (Murrill),  and  was 
first  observed  in  the  vicinity  of  New  York  in  1905.  At  that 
time  only  a  few  trees  were  known  to  have  been  killed  by 
this  disease,  but  now  the  disease  has  advanced  over  the 
whole  chestnut  area  in  the  United  States,  reaching  as  far 
south  as  Virginia  and  as  far  west  as  Buffalo.  Fig.  Ill 
shows  the  result  of  the  chestnut  disease. 

The  fungus  attacks  the  cambium  tissue  underneath 
the  bark.  It  enters  through  a  wound  in  the  bark  and 
sends  its  fungous  threads  from  the  point  of  infection  all 
around  the  trunk  until  the  latter  is  girdled  and  killed. 
This  may  all  happen  within  one  season.  It  is  not  until 
the  tree  has  practically  been  destroyed  that  the  disease 
makes  its  appearance  on  the  surface  of  the  bark  in  the 
form  of  brown  patches  studded  with  little  pustules  that 
carry  the  spores.  When  once  girdled,  the  tree  is  killed 
above  the  point  of  infection  and  everything  above  dies, 
while  some  of  the  twigs  below  may  live  until  they  are 
attacked  individually  by  the  disease  or  until  the  trunk 
below  their  origin  is  infected. 

All  species  of  chestnut  trees  are  subject  to  the  disease. 
The  Japanese  and  Spanish  varieties  appear  to  be  highly 
resistant,  but  are  not  immune.  Other  species  of  trees 
besides  chestnuts  are  not  subject  to  the  disease. 


TREE  DISEASES 


159 


There  is  no  remedy  or  preventive  for  this  disease.     From 
the  nature  of  its  attack,  which  is  on  the  inner  layer  of  the 


FIG.  111.— Chestnut  Trees  Killed  by  the  Chestnut  Disease. 


tree,  it  is  evident  that  all  applications  of  fungicides,  which 
must  necessarily  be  applied  to  the  outside  of  the  tree, 
will  not  reach  the  disease.  Injections  are  impossible  and 


160  STUDIES  OF  TREES 

other  suggested  remedies,  such  as  boring  holes  in  the  wood 
for  the  purpose  of  inserting  chemicals,  are  futile. 

The  wood  of  the  chestnut  tree,  within  three  or  four  years 
after  its  death,  is  still  sound  and  may  be  used  for  telephone 
and  telegraph  poles,  posts,  railroad  ties,  lumber  and 
firewood. 

Spraying  for  fungous  diseases :  Where  a  fungous  disease 
is  attacking  the  leaves,  fruit,  or  twigs,  spraying  with 
Bordeaux  mixture  may  prove  effective.  The  application 
of  Bordeaux  mixture  is  deterrent  rather  than  remedial, 
and  should  therefore  be  made  immediately  before  the 
disease  appears.  The  nature  of  the  disease  and  the  time 
of  treatment  can  be  determined  without  cost,  by  submitting 
specimens  of  affected  portions  of  the  plant  for  analysis 
and  advice  to  the  State  Agricultural  Experiment  Station 
or  to  the  United  States  Department  of  Agriculture. 

Bordeaux  mixture,  the  standard  fungicide  material, 
consists  of  a  solution  of  6  pounds  of  copper  sulphate  (blue 
vitriol)  with  4  pounds  of  slaked  lime  in  50  gallons  of 
water.  It  may  be  purchased  in  prepared  form  in  the  open 
market,  and  when  properly  made,  has  a  brilliant  sky-blue 
color.  Spraying  with  Bordeaux  mixture  should  be  done 
in  the  fall,  early  spring,  or  early  summer,  but  never  during 
the  period  when  the  trees  are  in  bloom. 

STUDY  HI.     PRUNING   TREES 
FUNDAMENTAL  PRINCIPLES 

Trees  are  very  much  like  human  beings  in  their  require- 
ments, mode  of  life  and  diseases,  and  the  general  principles 
applicable  to  the  care  of  one  are  equally  important  to  the 
intelligent  treatment  of  the  other.  The  removal  of  limbs 


PRUNING  TREES 


161 


from  trees,  as  well  as  from  human  beings,  must  be  done 
sparingly   and   judiciously.     Wounds,    in   both   trees   and 


FIG.  112. — A  Tree  Pruned  Improperly  and  too  Severely. 

human  beings,  must  be  disinfected  and  dressed  to  keep  out 
all  fungus  or  disease  germs.  Fungous  growths  of  trees 
are  similar  to  human  cancers,  both  in  the  manner  of  their 


162  STUDIES  OF  TREES 

development  and  the  surgical  treatment  which  they  require. 
Improper  pruning  will  invite  fungi  and  insects  to  the  tree, 
hence  the  importance  of  a  knowledge  of  fundamental 
principles  in  this  branch  of  tree  care. 

Time:  Too  much  pruning  at  one  time  should  never 
be  practiced  (Fig.  112),  and  no  branch  should  be  removed 
from  a  tree  without  good  reason  for  so  doing.  Dead  and 
broken  branches  should  be  removed  as  soon  as  observed, 
regardless  of  any  special  pruning  season,  because  they  are 
dangerous,  unsightly  and  carry  insects  and  disease  into  the 
heart  of  the  tree.  But  all  other  pruning,  whether  it  be  for 
the  purpose  of  perfecting  the  form  in  shade  trees,  or  for 
increasing  the  production  of  fruit  in  orchard  trees,  should 
be  confined  to  certain  seasons.  Shade  and  ornamental 
trees  can  best  be  pruned  in  the  fall,  while  the  leaves  are 
still  on  the  tree  and  while  the  tree  itself  is  in  practically 
a  dormant  state. 

Proper  cutting:  All  pruning  should  be  commenced 
at  the  top  of  the  tree  and  finished  at  the  bottom.  A 
shortened  branch  (excepting  in  poplars  and  willows,  which 
should  be  cut  in  closely)  should  terminate  in  small  twigs 
which  may  draw  the  sap  to  the  freshly  cut  wound;  where 
a  branch  is  removed  entirely,  the  cut  should  be  made 
close  and  even  with  the  trunk,  as  in  Fig.  113.  Wher- 
ever there  is  a  stub  left  after  cutting  off  a  branch,  the 
growing  tissue  of  the  tree  cannot  cover  it  and  the  stub 
eventually  decays,  falls  out  and  leaves  a  hole  (see  Fig. 
114),  which  serves  to  carry  disease  and  insects  to  the 
heart  of  the  tree.  This  idea  of  close  cutting  cannot  be 
over-emphasized. 

Where  large  branches  have  to  be  removed,  the  splitting 
and  ripping  of  the  bark  along  the  trunk  is  prevented  by 
making  one  cut  beneath  the  branch,  about  a  foot  or  two 


PRUNING  TREES 


163 


away  from  the  trunk,  and  then  another  above,  close  to  the 
trunk. 


FIG.  113.— Branches  Properly  Cut  Close  to  the  Trunk. 


Too  severe  pruning:  In  pruning  trees,  many  people 
have  a  tendency  to  cut  them  back  so  severely  as  to  remove 
everything  but  the  bare  trunk  and  a  few  of  the  main 


164 


STUDIES  OF  TREES 


branches.  This  process  is  known  as  "  heading  back."  It 
is  a  method,  however,  which  should  not  be  resorted  to 
except  in  trees  that  are  very  old  and  failing,  and  even 
there  only  with  certain  species,  like  the  silver  maple,  syca- 


FIQ.  114. — A  Limb  Improperly  Cut.     Note  how  the  stub  is  decaying 
and  the  resulting  cavity  is  becoming  diseased. 


more,  linden  and  elm.  Trees  like  the  sugar  maple  will  not 
stand  this  treatment  at  all.  The  willow  is  a  tree  that 
will  stand  the  process  very  readily  and  the  Carolina  poplar 
must  be  cut  back  every  few  years,  in  order  to  keep  its  crown 
from  becoming  too  tall,  scraggy  and  unsafe. 

Covering    wounds:    The    importance    of    immediately 


PRUNING  TREES 


165 


covering  all  wounds  with  coal  tar  cannot  be  overstated. 
If  the  wound  is  not  tarred,  the  exposed  wood  cracks,  .as  in 
Fig.  115,  providing  suitable  quarters  for  disease  germs 
that  will  eventually  destroy  the  body  of  the  tree.  Coal  tar 


FIG.  115.— Result  of  a  Wound  not  Covered  with  Coal  Tar. 
The  exposed  wood  cracked  and  decay  set  in. 

is  by  far  preferable  to  paint  and  other  substances  for  covering 
the  wound.  The  tar  penetrates  the  exposed  wood,  pro- 
ducing an  antiseptic  as  well  as  a  protective  effect.  Paint 
only  forms  a  covering,  which  may  peel  off  in  course  of  time 
and  which  will  later  protrude  from  the  cut,  thus  forming, 
between  the  paint  and  the  wood,  a  suitable  breeding  place 


166  STUDIES  OF  TREES 

for  the  development  of  destructive  fungi  or  disease.  The 
application  of  tin  covers,  burlap,  or  other  bandages  to  the 
wound  is  equally  futile  and  in  most  cases  even  injurious. 

SPECIAL  CONSIDERATIONS 

Prumug  shade  trees:  Here,  the  object  is  to  produce  a 
symmetrical  crown  and  to  have  the  lowest  branches  raised 
from  the  ground  sufficiently  high  to  enable  pedestrians 
to  pass  under  with  raised  umbrellas.  Such  pruning  should, 
therefore,  necessarily  be  light  and  confined  to  the  low 
limbs  and  dead  branches. 

Pruning  lawn  trees:  Here  the  charm  of  the  tree  lies 
in  the  low  reach  of  the  branches  and  the  compactness 
of  the  crown.  The  pruning  should,  therefore,  be  limited 
to  the  removal  of  dead  and  diseased  branches  only. 

Pruning  forest  trees :  Forest  trees  have  a  greater  com- 
mercial value  when  their  straight  trunks  are  free  from 
branches.  In  the  forest,  nature  generally  accomplishes  this 
result  and  artificial  pruning  seldom  has  to  be  resorted  to. 
Trees  in  the  forest  grow  so  closely  together  that  they  shut  out 
the  sunlight  from  their  lower  limbs,  thus  causing  the  latter 
to  die  and  fall  off.  This  is  known  as  natural  pruning.  In 
some  European  forests,  nature  is  assisted  in  its  pruning  by 
workmen,  who  saw  off  the  side  branches  before  they  fall 
of  their  own  accord;  but  in  this  country  such  practice  would 
be  considered  too  expensive,  hence  it  is  seldom  adopted. 

TOOLS  USED  IN  PRUNING 

Good  tools  are  essential  for  quick  and  effective  work  in 
pruning.  Two  or- three  good  saws,  a  pair  of  pole-shears,  a 
pole-saw,  a  16-foot  single  ladder,  a  40-foot  extension  ladder 


PRUNING  TREES  167 

of  light  spruce  or  pine  with  hickory  rungs,  a  good  pruning 
knife,  plenty  of  coal  tar,  a  fire-can  to  heat  the  tar,  a  pole- 
brush,  a  small  hand  brush  and  plenty  of  good  rope  com- 
prise the  principal  equipment  of  the  pruner. 

SUGGESTIONS  FOR  THE  SAFETY  OF  TREE  CLIMBERS 

1.  Before  climbing  a  tree,  judge  its  general  condition. 
The  trunk  of  a  tree  that  shows  age,  disease,  or  wood- 
destroying  insects  generally  has  its  branches  in  an  equally 
unhealthy  condition. 

2.  The  different  kinds  of  wood  naturally  differ  in  their 
strength  and  elasticity.  The  soft  and  brash  woods  need 
greater  precautions  than  the  strong  and  pliable  ones.  The 
wood  of  all  the  poplars,  the  ailanthus,  the  silver  maple 
and  the  chestnut,  catalpa  and  willow  is  either  too  soft  or 
too  brittle  to  be  depended  upon  without  special  care.  The 
elm,  hickory  and  oak  have  strong,  flexible  woods  and  are, 
therefore,  safer  than  others.  The  red  oak  is  weaker  than  the 
other  oaks.  The  sycamore  and  beech  have  a  tough,  cross- 
grained  wood  which  is  fairly  strong.  The  linden  has  a 
soft  wood,  while  the  ash  and  gum,  though  strong  and  flexible, 
are  apt  to  split. 

3.  Look  out  for  a  limb  that  shows  fungous  growths. 
Every  fungus  sends  fibers  into  the  main  body  of  the  limb 
which  draw  out  its  sap.     The  interior  of  the  branch  then 
loses   its   strength   and  becomes   like   a  powder.     Outside 
appearances  sometimes  do  not  show  the  interior  condition, 
but  one  should  regard  a  fungus  as  a  danger  sign. 

4.  When  a  limb  is  full  of  holes  or  knots,  it  generally 
indicates  that  borers  have  been  working  all  kinds  of  gal- 
leries through  it,  making  it  unsafe.     The  silver  maple  and 
sycamore   maple   are   especially   subject   to   borers   which, 


168  STUDIES  OF  TREES 

in  many  cases,  work  on  the  under  side  of  the  branch  so  that 
the  man  in  the  tree  looking  down  cannot  see  its  dangerous 
condition. 

5.  A  dead  limb  with  the  bark  falling  off  indicates  that  it 
died  at  least  three  months  before  and  is,  therefore,  less 
safe  than  one  with  its  bark  tightly  adhering  to  it. 

6.  Branches  are  more  apt  to  snap  on  a  frosty  day  when 
they  are  covered  with  an  icy  coating  than  on  a  warm 
summer  day. 

7.  Always  use  the  pole-saw  and  pole-shears  on  the  tips 
of  long  branches,  and  use  the  pole-hook  in  removing  dead 
branches  of  the  ailanthus  and  other  brittle  trees  where  it 
would  be  too  dangerous  to  reach  them  otherwise. 

8.  Be  sure  of  the  strength  of  a  branch  before  tying  an 
extension  ladder  to  it. 


STUDY  IV.     TREE   REPAIR 

Where  trees  have  been  properly  cared  for  from  their 
early  start,  wounds  and  cavities  and  their  subsequent 
elaborate  treatment  have  no  place.  But  where  trees  have 
been  neglected  or  improperly  cared  for,  wounds  and  cavities 
are  bound  to  occur  and  early  treatment  becomes  a  necessity. 

There  are  two  kinds  of  wounds  on  trees:  (1)  surface 
wounds,  which  do  not  extend  beyond  the  inner  bark,  and 
(2)  deep  wounds  or  cavities,  which  may  range  from  a  small 
hole  in  a  crotch  to  the  hollow  of  an  entire  trunk. 

Surface  wounds:  Surface  wounds  (Fig.  116)  are  due 
to  bruised  bark,  and  a  tree  thus  injured  can  no  longer  pro- 
duce the  proper  amount  of  foliage  or  remain  healthy  very 
long.  The  reason  for  this  becomes  very  apparent  when 
one  looks  into  the  nature  of  the  living  or  active  tissue  of  a 


TREE  REPAIR 


169 


tree  and  notes  how  this  tissue  be- 
comes affected  by  such  injuries. 

This  living  or  active  tissue  is 
known  as  the  "  cambium  layer," 
and  is  a  thin  tissue  situated 
immediately  under  the  bark. 
It  must  completely  envelop  the 
stem,  root  and  branches  of  the 
trees.  The  outer  bark  is  a 
protective  covering  to  this  liv- 
ing layer,  while  the  entire  inte- 
rior wood  tissue  chiefly  serves 
as  a  skeleton  or  support  for 
the  tree.  The  cambium  layer 
is  the  real,  active  part  of  the 
tree.  It  is  the  part  which 
transmits  the  sap  from  the  base 
of  the  tree  to  its  crown;  it  is 
the  part  which  causes  the  tree 
to  grow  by  the  formation  of  new 
cells,  piled  up  in  the  form  of 
rings  around  the  heart  of  the 
tree;  and  it  is  also  the  part 
which  prevents  the  entrance  of 
insects  and  disease  to  the  inner 
wood.  From  this  it  is  quite 
evident  that  any  injury  to  the 
bark,  and  consequently  to  this 
cambium  layer  alongside  of  it, 

will  not  only  cut  off  a  portion  of  the  sap  supply  and 
hinder  the  growth  of  the  tree  to  arr  extent  proportional 
to  the  size  of  the  wound,  but  will  also  expose  the  inner  wood 
to  the  action  of  decay.  The  wound  may,  at  first,  appear 


FIG.  116.— A  Surface  Wound 
Properly  Freed  from  De- 
cayed Wood  and  Covered 
with  Coal  Tar. 


170  STUDIES  OF  TREES 

insignificant,  but,  if  neglected,  it  will  soon  commence  to 
decay  and  thus  to  carry  disease  and  insects  into  the  tree. 
The  tree  then  becomes  hollow  and  dangerous  and  its  life 
is  doomed. 

Injury  to  the  cambium  layer,  resulting  in  surface  wounds, 
may  be  due  to  the  improper  cutting  of  a  branch,  to  the 
tite  of  a  horse,  to  the  cut  of  a  knife  or  the  careless  wielding 
of  an  axe,  to  the  boring  of  an  insect,  or  to  the  decay  of  a 
fungous  disease.  (See  Fig.  117.)  Whatever  the  cause, 
the  remedy  lies  in  cleaning  out  all  decayed  wood,  removing 
the  loose  bark  and  covering  the  exposed  wood  with  coal  tar. 

In  cutting  off  the  loose  bark,  the  edges  should  be  made 
smooth  before  the  coal  tar  is  applied.  Loose  bark,  put 
back  against  a  tree,  will  never  grow  and  will  only  tend  to 
harbor  insects  and  disease.  Bandages,  too,  are  hurtful 
because,  underneath  the  bandage,  disease  will  develop  more 
rapidly  than  where  the  wound  is  exposed  to  the  sun  and  wind. 
The  application  of  tin  or  manure  to  wounds  is  often  indulged 
in  and  is  equally  injurious  to  the  tree.  The  secret  of  all 
wound  treatment  is  to  keep  the  wound  smooth,  clean  to  the 
live  tissue,  and  well  covered  with  coal  tar. 

The  chisel  or  gouge  is  the  best  tool  to  employ  in  this 
work.  A  sharp  hawk-billed  knife  will  be  useful  in  cutting 
off  the  loose  bark.  Coal  tar  is  the  best  material  for  cover- 
ing wounds  because  it  has  both  an  antiseptic  and  a  pro- 
tective effect  on  the  wood  tissue.  Paint,  which  is  very 
often  used  as  a  substitute  for  coal  tar,  is  not  as  effective, 
because  the  paint  is  apt  to  peel  in  time,  thus  allowing 
moisture  and  disease  to  enter  the  crevice  between  the 
paint  and  the  wood. 

Cavities:  Deep  wounds  and  cavities  are  generally  the 
result  of  stubs  that  have  been  permitted  to  rot  and  fall  out. 
Surface  wounds  allowed  to  decay  will  deepen  in  course  of 


TREE  REPAIR 


171 


FIG.  117. — A  Neglected  Surface  Wound.  Note  the  rough  surface  of 
the  wound,  the  want  of  a  coal  tar  covering  and  the  fungous  growth 
that  followed. 


172  STUDIES  OF  TREES 

time  and  produce  cavities.  Cavities  in  trees  are  especially 
susceptible  to  the  attack  of  disease  because,  in  a  cavity, 
there  is  bound  to  exist  an  accumulation  of  moisture.  With 
this,  there  is  also  considerable  darkness  and  protection 
from  wind  and  cold,  and  these  are  all  ideal  conditions  for 
the  development  of  disease. 

The  successful  application  of  a  remedy,  in  all  cavity 
treatment,  hinges  on  this  principal  condition — that  all 
traces  of  disease  shall  be  entirely  eliminated  before  treatment 
is  commenced. 

Fungous  diseases  attacking  a  cavity  produce  a  mass  of 
fibers,  known  as  the  "  mycelium,"  that  penetrate  the  body 
of  the  tree  or  limb  on  which  the  cavity  is  located.  In 
eliminating  disease  from  a  cavity,  it  is,  therefore,  essential 
to  go  beyond  the  mere  decaying  surface  and  to  cut  out  all 
fungous  fibers  that  radiate  into  the  interior  of  the  tree. 
Where  these  fibers  have  penetrated  so  deeply  that  it  becomes 
impossible  to  remove  every  one  of  them,  the  tree  or  limb 
thus  affected  had  better  be  cut  down.  (Fig.  118.)  The 
presence  of  the  mycelium  in  wood  tissue  can  readily  be  told 
by  the  discolored  and  disintegrated  appearance  of  the  wood. 

The  filling  in  a  cavity,  moreover,  should  serve  to  prevent 
the  accumulation  of  water  and,  where  a  cavity  is  perpen- 
dicular and  so  located  that  the  water  can  be  drained  off 
without  the  filling,  the  latter  should  be  avoided  and  the 
cavity  should  merely  be  cleaned  out  and  tarred.  (Fig.  116.) 
Where  the  disease  can  be  entirely  eliminated,  where  the 
cavity  is  not  too  large,  and  where  a  filling  will  serve  the 
practical  purpose  of  preventing  the  accumulation  of  moisture, 
the  work  of  filling  should  be  resorted  to. 

Filling  should  be  done  in  the  following  manner:  First, 
the  interior  should  be  thoroughly  freed  from  diseased 
wood  and  insects.  The  chisel,  gouge,  mall  and  knife  are 


TREE  EEPAIR 


173 


FIG.  118.— A  Cavity  Filled  in  a  Tree  that  Should  Have  Been  Cut 
Down.  Note  how  the  entire  interior  is  decayed  and  how  the  tree 
fell  apart  soon  after  treatment. 


174 


STUDIES  OF  TREES 


the  tools,  and  it  is  better  to  cut  deep  and  remove  every 
trace  of  decayed  wood  than  it  is  to  leave  a  smaller  hole  in  an 


FIG.  119. — A  Cavity  in  the  Process  of  being  Filled. 

unhealthy  state.   The  inner  surface  of  the  cavity  should  then 
be  covered  with  a  coat  of  white  lead  paint,  which  acts  as  a 


TREE  REPAIR 


175 


disinfectant  and  helps  to  hold  the  filling.    Corrosive  sublim- 
ate or  Bordeaux  mixture  may  be  used  as  a  substitute  for  the 


FIG.  120.— The  Same  Cavity  Properly  Filled. 

white  lead  paint.     A  coat  of  coal  tar  over  the  paint  is  the 
next  step.     The  cavity  is  then  solidly  packed  with  bricks, 


176  STUDIES  OF  TREES 

stones  and  mortar  as  in  Fig.  119,  and  finished  with  a  layer 
of  cement  at  the  .nouth  of  the  orifice.  This  surface  layer 
of  cement  should  not  be  brought  out  to  the  same  plane 
with  the  outer  bark  of  the  tree,  but  should  rather  recede 
a  little  beyond  the  growing  tissue  (cambium  layer)  which 
is  situated  immediately  below  the  bark,  Fig.  120.  In  this 
way  the  growing  tissue  will  be  enabled  to  roll  over  the 
cement  and  to  cover  the  whole  cavity  if  it  be  a  small  one, 
or  else  to  grow  out  sufficiently  to  overlap  the  filling  and 
hold  it  as  a  frame  holds  a  picture.  The  cement  is  used  in 
mixture  with  sand  in  the  proportion  of  one-third  of  cement 
to  two-thirds  of  sand.  When  dry,  the  outer  layer  of  cement 
should  be  covered  with  coal  tar  to  prevent  cracking. 

Trees  that  tend  to  split:  Certain  species  of  trees,  like 
the  linden  and  elm,  often  tend  to  split,  generally  in  the  crotch 
of  several  limbs  and  sometimes  in  a  fissure  along  the  trunk  of 
the  tree.  Midwinter  is  the  period  when  this  usually  occurs 
and  timely  action  will  save  the  tree.  The  remedy  lies  in 
fastening  together  the  various  parts  of  the  tree  by  means  of 
bolts  or  chains. 

A  very  injurious  method  of  accomplishing  this  end  is 
frequently  resorted  to,  where  each  of  the  branches  is  bound 
by  an  iron  band  and  the  bands  are  then  joined  by  a  bar. 
The  branches  eventually  outgrow  the  diameter  of  the  bands, 
causing  the  latter  to  cut  through  the  bark  of  the  limbs  and 
to  destroy  them. 

Another  method  of  bracing  limbs  together  consists  in 
running  a  single  bolt  through  them  and  fastening  each  end 
of  the  bolt  with  a  washer  and  nut.  This  method  is  prefer- 
able to  the  first  because  it  allows  for  the  growth  of  the  limbs 
in  thickness. 

A  still  better  method,  however,  consists  in  using  a  bar 
composed  of  three  parts  as  shown  in  Fig.  121.  Each  of  the 


TREE  REPAIR 


177 


two  branches  has  a  short  bolt  passed  through  it  horizontally, 
and  the  two  short  bolts  are  then  connected  by  a  third  bar. 
This  arrangement  will  shift  all  the  pressure  caused  by  the 
swaying  of  the  limbs  to  the  middle  connecting-bar.  In 


FIG.  121. — Diagram  Showing  the  Triple-bar  Method  of 
Fastening  Limbs. 


case  of  a  wind-storm,  the  middle  bar  will  be  the  one  to  bend, 
while  the  bolts  which  pass  through  the  limbs  will  remain 
intact.  The  outer  ends  of  the  short  bolts  should  have 
their  washers  and  nuts  slightly  embedded  in  the  wood  of  the 
tree,  so  that  the  living  tissue  of  the  tree  may  eventually 
grow  over  them  in  such  a  way  as  to  hold  the  bars  firmly 


178  STUDIES  OF  TREES 

in  place  and  to  exclude  moisture  and  disease.  The  washers 
and  nuts  on  the  inner  side  of  the  limbs  should  also  be 
embedded. 

A  chain  is  sometimes  advantageously  substituted  for 
the  middle  section  of  the  bar  and,  in  some  cases,  where 
more  than  two  branches  have  to  be  joined  together,  a  ring 
might  take  the  place  of  the  middle  bar  or  chain. 

Bolts  on  a  tree  detract  considerably  from  its  natural 
beauty  and  should,  therefore,  be  used  only  where  they 
are  absolutely  necessary  for  the  safety  of  the  tree.  They 
should  be  placed  as  high  up  in  the  tree  as  possible  without 
weakening  the  limbs. 


CHAPTER  VII 

FORESTRY 
STUDY  I.     WHAT   FORESTRY  IS  AND  WHAT  IT  DOES 

Although  Forestry  is  not  a  new  idea  but,  as  a  science 
and  an  art,  has  been  applied  for  nearly  two  thousand  years, 
there  are  many  persons  who  still  need  an  explanation  of 
its  aims  and  principles. 

Forestry  deals  with  the  establishment,  protection  and 
utilization  of  forests. 

By  establishment,  is  meant  the  planting  of  new  forests  and 
the  cutting  of  mature  forests,  in  such  a  way  as  to  encourage 
a  natural  growth  of  new  trees  without  artificial  planting  or 
seeding.  The  planting  may  consist  of  sowing  seed,  or  of 
setting  out  young  trees.  The  establishment  of  a  forest  by 
cutting  may  consist  of  the  removal  of  all  mature  trees  and 
dependence  upon  the  remaining  stumps  to  reproduce  the 
forest  from  sprouts,  or  it  may  consist  of  the  removal  of  only 
a  portion  of  the  mature  trees,  thus  giving  the  young  seedlings 
on  the  ground  room  in  which  to  grow. 

By  protection,  is  meant  the  safeguarding  of  the  forest 
from  fire,  wind,  insects,  disease  and  injury  for  which  man 
is  directly  responsible.  Here,  the  forester  also  prevents 
injury  to  the  trees  from  the  grazing  and  browsing  of  sheep 
and  goats,  and  keeps  his  forest  so  well  stocked  that  no  wind 
can  uproot  the  trees  nor  can  the  sun  dry  up  the  moist 
forest  soil. 

179 


180 


STUDIES  OF  TREES 


By  utilization,  is  meant  the  conservative  and  intelligent 
harvesting  of  the  forest,  with  the  aim  of  obtaining  the 
greatest  amount  of  product  from  a  given  area,  with  the 
least  waste,  in  the  quickest  time,  and  without  the  slightest 
deterioration  of  the  forest  as  a  whole.  The  forester  cuts 


FIG.  122.— A  Forest  of  Bull  Pine  Cut  on  Forestry  Principles.    (Photo- 
graph taken  on  the  Black  Hills  National  Forest,  South  Dakota.) 


his  mature  trees,  only,  and  generally  leaves  a  sufficient 
number  on  the  ground  to  preserve  the  forest  soil  and  to 
cast  seed  for  the  production  of  a  new  crop.  In  this  way,  he 
secures  an  annual  output  without  hurting  the  forest  itself. 
He  studies  the  properties  and  values  of  the  different  woods 
and  places  them  where  they  will  be  most  useful.  He  lays 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES        181 


FIG.  123.— A  White  Pine  Plantation,  in  Rhode  Island,  Where  tLe 
Crowns  of  the  Trees  Have  Met.  The  trees  are  fifteen  years  old 
and  in  many  cases  every  other  tree  had  to  be  removed. 


182  STUDIES  OF  TREES 

down  principles  for  so  harvesting  the  timber  and  the  by-prod- 
ucts of  the  forest  that  there  will  be  the  least  waste  and 
injury  to  the  trees  which  remain  standing.  He  utilizes 
the  forest,  but  does  not  cut  enough  to  interfere  with  the 
neighboring  water-sheds,  which  the  forests  protect. 

Forestry,  therefore,  deals  with  a  vast  and  varied  mass  of 
information,  comprising  all  the  known  facts  relating  to  the 
life  of  a  forest.  It  does  not  deal  with  the  individual  tree 
and  its  planting  and  care, — that  would  be  arboriculture. 
Nor  does  it  consider  the  grouping  of  trees  for  aesthetic 
effect, — that  would  be  landscape  gardening.  It  concerns 
itself  with  the  forest  as  a  community  of  trees  and  with  the 
utilization  of  the  forest  on  an  economic  basis. 

Each  one  of  these  activities  in  Forestry  is  a  study  in 
itself  and  involves  considerable  detail,  of  which  the  reader 
may  obtain  a  general  knowledge  in  the  following  pages. 
For  a  more  complete  discussion,  the  reader  is  referred  to 
any  of  the  standard  books  on  Forestry. 

The  life  and  nature  of  a  forest:  When  we  think  of  a 
forest  we  are  apt  to  think  of  a  large  number  of  individual 
trees  having  no  special  relationship  to  each  other.  Closer 
observation,  however,  will  reveal  that  the  forest  consists 
of  a  distinct  group  of  trees,  sufficiently  dense  to  form  an 
unbroken  canopy  of  tops,  and  that,  where  trees  grow  so 
closely  together,  they  become  very  interdependent.  It 
is  this  interdependence  that  makes  the  forest  different 
from  a  mere  group  of  trees  in  a  park  or  on  a  lawn.  In 
this  composite  character,  the  forest  enriches  its  own  soil 
from  year  to  year,  changes  the  climate  within  its  own  bounds, 
controls  the  streams  along  its  borders  and  supports  a 
multitude  of  animals  and  plants  peculiar  to  itself.  This 
communal  relationship  in  the  life  history  of  the  forest 
furnishes  a  most  interesting  story  of  struggle  and  mutual 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES        183 

aid.  Different  trees  have  different  requirements  with 
regard  to  water,  food  and  light.  Some  need  more  water 
and  food  than  others,  some  will  not  endure  much  shade, 
and  others  will  grow  in  the  deepest  shade.  In  the  open, 
a  tree,  if  once  established,  can  meet  its  needs  quite  readily 


FIG.  124. — Measuring  the  Diameter  of  a  Tree  and  Counting 
its  Annual  Rings. 

and,  though  it  has  to  ward  off  a  number  of  enemies, 
insects,  disease  and  windstorm — its  struggle  for  existence 
is  comparatively  easy.  In  the  forest,  the  conditions  are 
different.  Here,  the  tree-enemies  have  to  be  battled 
with,  just  as  in  the  open,  and  in  addition,  instead  of  there 
being  only  a  few  trees  on  a  plot  of  ground,  there  are  thousands 


184  STUDIES  OF  TREES 

growing  on  the  same  area,  all  demanding  the  same  things 
out  of  a  limited  supply.  The  struggle  for  existence,  there- 
fore, becomes  keen,  many  falling  behind  and  but  few  sur- 
viving. 

This  struggle  begins  with  the  seed.  At  first  there  are 
thousands  of  seeds  cast  upon  a  given  area  by  the  neighboring 
trees  or  by  the  birds  and  the  winds.  Of  these,  only  a  few 
germinate;  animals  feed  on  some  of  them,  frost  nips  some 
and  excessive  moisture  and  unfavorable  soil  conditions 
prevent  others  from  starting.  The  few  successful  ones 
soon  sprout  into  a  number  of  young  trees  that  grow  thriftily 
until  their  crowns  begin  to  meet.  When  the  trees  have 
thus  met,  the  struggle  is  at  its  height.  The  side  branches 
encroach  upon  each  other  (Fig.  123),  shut  out  the  light 
without  which  the  branches  cannot  live,  and  finally  kill 
each  other  off.  The  upper  branches  vie  with  one  another 
for  light,  grow  unusually  fast,  and  the  trees  increase  in 
height  with  special  rapidity.  This  is  nature's  method  of 
producing  clear,  straight  trunks  which  are  so  desirable  for 
poles  and  large  timber.  In  this  struggle  for  dominance, 
some  survive  and  tower  above  the  others,  but  many  become 
stunted  and  fail  to  grow,  wrhile  the  majority  become  entirely 
overtopped  and  succumb  in  the  struggle;  see  Fig.  139. 
>•  But  in  this  strife  there  is  also  mutual  aid.  Each  tree 
helps  to  protect  its  neighbors  against  the  danger  of  being 
uprooted  by  the  wind,  and  against  the  sun,  which  is  liable 
to  dry  up  the  rich  soil  around  the  roots.  This  soil  is  different 
from  the  soil  on  the  open  lawn.  It  consists  of  an  accumula- 
tion of  decayed  leaves  mixed  with  inorganic  matter,  forming, 
together,  a  rich  composition  known  as  humus.  The  trees 
also  aid  each  other  informing  a  close  canopy  that  prevents 
the  rapid  evaporation  of  water  from  the  ground. 

The  intensity  of  these  conditions  will  vary  a  great  deal 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       185 

with  the  composition  of  the  forest  and  the  nature  and 
habits  of  the  individual  trees.  By  composition,  or  type 
of  forest,  is  meant  the  proportion  in  which  the  various 
species  of  trees  are  grouped;  i.e.,  whether  a  certain  section 
of  woodland  is  composed  of  one  species  or  of  a  mixture  of 
species.  By  habit  is  meant  the  requirements  of  the  trees 
for  light,  water  and  food. 


FIG.  125. — Mountain  Slopes  in  North  Carolina  Well  Covered 
with  Forests. 

Some  trees  will  grow  in  deep  shade  while  others  will 
demand  the  open.  In  the  matter  of  water  and  food,  the 
individual  requirements  of  different  trees  are  equally 
marked. 

The  natural  rapidity  of  growth  of  different  species  is 
also  important,  and  one  caring  for  a  forest  must  know 
this  rate  of  growth,  not  only  as  to  the  individual  species, 
but  also  with  respect  to  the  forest  as  a  whole.  If  he  knows 


186 


STUDIES  OF  TREES 


how  fast  the  trees  in  a  forest  grow,  both  in  height  and 
diameter,  he  will  know  how  much  wood,  in  cubic  feet,  the 
forest  produces  in  a  year,  and  he  can  then  determine  how 
much  he  may  cut  without  decreasing  the  capital  stock. 
The  rate  of  growth  is  determined  in  this  way:  A  tree  is 


FIG.  126. — Bottom  Lands  Buried  in  Waste  from  Deforested  Mountains. 
Wu-t'ai-shan,  Shan-si  Province,  China. 


cut  and  the  rings  on  the  cross-section  surface  are  counted 
and  measured;  see  -Fig.  124.  Each  ring  represents  one 
year's  growth.  The  total  number  of  rings  will  show  the 
age  of  the  tree.  By  a  study  of  the  rings  of  the  various 
species  of  trees  on  a  given  plot,  the  rate  of  growth  of  each 
species  in  that  location  can  be  ascertained  and,  by  knowing 
the  approximate  number  of  trees  of  each  species  on  the 


WHAT   FORESTRY  IS  AND  WHAT  IT  DOES        187 

forest  area,  the  rate  of  growth  of  the  whole  forest  for  any 
given  year  can  be  determined. 

Forests  prevent  soil  erosion  and  floods:  Forests  help 
to  regulate  the  flow  of  streams  and  prevent  floods.  Most 
streams  are  bordered  by  vast  tracts  of  forest  growths. 


FIG.  127.— Eroded  Slope  in  Western  North  Carolina. 

The  rain  that  falls  on  these  forest  areas  is  absorbed  and 
held  by  the  forest  soil,  which  is  permeated  with  decayed 
leaves,  decayed  wood  and  root  fibers.  The  forest  floor  is, 
moreover,  covered  with  a  heavy  undergrowth  and  thus 
behaves  like  a  sponge,  absorbing  the  water  that  falls  upon 
it  and  then  permitting  it  to  ooze  out  gradually  to  the  valleys 
and  rivers  below.  A  forest  soil  will  retain  one-half  of  its 


188 


STUDIES  OF  TREES 


own  quantity  of  water;  i.e.,  for  every  foot  in  depth  of  soil 
there  can  be  six  inches  of  water  and,  when  thus  saturated, 
the  soil  will  act  as  a  vast,  underground  reservoir  from  which 
the  springs  and  streams  are  supplied  (Fig.  125).  Cut  the 
forest  down  and  the  land  becomes  such  a  desert  as  is  shown 
in  Fig.  126.  The  soil,  leaves,  branches  and  fallen  trees 


FIG.  128.— Flood  in  Pittsburgh,  Pa. 


dry  to  dust,  are  carried  off  by  the  wind  and,  with  the  fall 
of  rain,  the  soil  begins  to  wash  away  and  gullies,  such  as 
are  shown  in  Fig.  127,  are  formed.  Streams  generally 
have  their  origins  in  mountain  slopes  and  there,  too,  the 
forests,  impeding  the  sudden  run  off  of  the  water  which  is 
not  immediately  absorbed,  prevent  soil  erosion. 

Where  the  soil  is  allowed  to  wash  off,  frequent  floods 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES        189 

are  inevitable.  Rain  which  falls  on  bare  slopes  is  not  caught 
by  the  crowns  of  trees  nor  held  by  the  forest  floor.  It  does 
not  sink  into  the  ground  as  readily  as  in  the  forest.  The  result 
is  that  a  great  deal  of  water  reaches  the  streams  in  a  short 
time  and  thus  hastens  floods.  At  other  periods  the  streams 
are  low  because  the  water  which  would  have  fed  them  for 
months  has  run  off  in  a  few  days.  The  farms  are  the  first 


FIG.  129. — Planting  a  Forest  with  Seedling  Trees  on  the  Nebraska 
National  Forest.  The  man  on  the  right  is  placing  the  tree  in  a 
slit  just  made  with  the  spade.  The  man  on  the  left  is  shoveling 
the  dry  sand  from  the  surface  before  making  the  slit  for  the  tree. 

to  suffer  from  the  drouths  that  follow  and,  during  the  period 
of  floods,  whole  cities  are  often  inundated.  Fig.  128 
shows  such  a  scene.  The  history  of  Forestry  is  full  of 
horrible  incidents  of  the  loss  of  life  and  property  from 
floods  which  are  directly  traceable  to  the  destruction  of 
the  local  forests  and,  on  the  other  hand,  there  are  many 
cases  on  record  where  flood  conditions  have  been  entirely 


190 


STUDIES  OF  TREES 


obviated  by  the  planting  of  forests.  France  and  Germany 
have  suffered  from  inundations  resulting  from  forest  devasta- 
tion and,  more  than  a  hundred  years  ago,  both  of  these 
countries  took  steps  to  reforest  their  mountain  slopes, 
and  thereby  to  prevent  many  horrible  disasters. 

How  forests   are    established:    New   forests   may   be 


FIG.  130. — Diagrammatic  Illustration  of  a  Selection  Forest. 

started  from  seed  or  from  shoots,  or  suckers.  If  from  seed, 
the  process  may  be  carried  on  in  one  of  three  ways: 

First,  by  sowing  the  seed  directly  on  the  land. 

Second,  by  first  raising  young  trees  in  nurseries  and  later 
setting  them  out  in  their  permanent  locations  in  the  forest. 
This  method  is  applicable  where  quick  results  are  desired, 
where  the  area  is  not  too  large,  or  in  treeless  regions  and 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       191 

large  open  gaps  where  there  is  little  chance  for  new  trees 
to  spring  up  from  seed  furnished  by  the  neighboring  trees. 
It  is  a  method  extensively  practiced  abroad  where  some  of 
the  finest  forests  are  the  result.  The  U.  S.  government,  as 
well  as  many  of  the  States,  maintain  forest-tree  nurseries 
where  millions  of  little  trees  are  grown  from  seed  and 
planted  out  on  the  National  and  State  forests.  Fig.  129 
shows  men  engaged  in  this  work.  The  fundamental  prin- 
ciples of  starting  and  maintaining  a  nursery  have  already 
been  referred  to  in  the  chapter  on  "  What  Trees  to  Plant 
and  How." 

The  third  method  of  establishing  a  forest  from  seed  is 
by  cutting  the  trees  in  the  existing  forest  so  that  the  seed 
falling  from  the  remaining  trees  will,  with  the  addition 
of  light  and  space,  readily  take  root  and  fill  in  the  gaps 
with  a  vigorous  growth  of  trees,  without  artificial  seeding 
or  planting.  This  gives  rise  to  several  methods  of  cutting 
or  harvesting  forests  for  the  purpose  of  encouraging  natural 
reproduction.  The  cutting  may  extend  to  single  trees 
over  the  whole  area  or  over  only  a  part  of  the  whole  area. 
Where  the  cutting  is  confined  to  single  trees,  the  system  is 
known  as  the  "  Selection  System,"  because  the  trees  are 
selected  individually,  with  a  view  to  retaining  the  best 
and  most  vigorous  stock  and  removing  the  overcrowding 
specimens  and  those  that  are  fully  mature  or  infested  with 
disease  or  insects. 

Fig.  130  is  a  diagrammatic  illustration  of  the  operation 
of  this  system.  In  another  system  the  cutting  is  done  in 
groups,  or  in  strips,  and  the  number  of  areas  of  the  groups 
or  strips  is  extended  from  time  to  time  until  the  whole 
forest  is  cleared.  This  system  is  illustrated  in  Fig.  131. 
Still  another  method  consists  in  encouraging  trees  which 
will  thrive  in  the  shade,  such  as  the  beech,  spruce  and 


192 


STUDIES  OF  TREES 


hemlock,  to  grow  under  light-demanding  trees  like  the 
pine.  This  system  presents  a  "  two-storied  "  forest  and 
is  known  by  that  name.  The  under  story  often  has  to  be 
established  by  planting. 

In  the   system  of  reproducing  forests  from   shoots  or 
suckers,  all  trees  of  a  certain  species  on  a  given  area  are 


FIG.  131. — Diagrammatic  Illustration  of  the  Group  or  Strip  System. 

cut  off  and  the  old  stumps  and  roots  are  depended  upon 
to  produce  a  new  set  of  sprouts,  the  strongest  of  which 
will  later  develop  into  trees.  The  coniferous  trees  do  not 
lend  themselves  at  all  to  this  system  of  treatment,  and, 
among  the  broadleaf  trees,  the  species  vary  in  their  ability 
to  sprout.  Some,  like  the  chestnut  and  poplar,  sprout 
profusely;  others  sprout  very  little. 

How    forests    are    protected:     Forestry    also    tries    to 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES      193 

protect  the  forests  from  many  destructive  agencies.  Wasteful 
lumbering  and  fire  are  the  worst  enemies  of  the  forest. 
Fungi,  insects,  grazing,  wind,  snow  and  floods  are  the  other 
enemies. 

By  wasteful  lumbering  is  meant  that  the  forest  is  cut 
with  no  regard  for  the  future  and  with  considerable  waste 


FIG.  132.— The  Result  of  a  Forest  Fire.  The  trees,  lodgepole  pine 
and  Englemann  spruce,  are  all  dead  and  down.  Photograph  taken 
in  the  Colorado  National  Forest,  Colorado. 

in  the  utilization  of  the  product.  Conservative  lumbering, 
which  is  the  term  used  by  foresters  to  designate  the  opposite 
of  wasteful  lumbering,  will  be  described  more  fully  later 
in  this  study. 

Protection  from  fire  is  no  less  important  than  protection 
from  wasteful  lumbering.  Forest  fires  are  very  common 
in  this  country  and  cause  incalculable  destruction  to  life 


194  STUDIES  OF  TREES 

and  property;  see  Fig.  132.  From  ten  to  twelve  million 
acres  of  forest-land  are  burnt  over  annually  and  the  timber 
destroyed  is  estimated  at  fifty  millions  of  dollars.  The 
history  of  Forestry  abounds  in  tales  of  destructive  fires, 
where  thousands  of  persons  have  been  killed  or  left  desti- 
tute, whole  towns  wiped  out,  and  millions  of  dollars  in 
property  destroyed.  In  most  cases,  these  uncontrollable 
fires  started  from  small  conflagrations  that  could  readily, 
with  proper  fire-patrol,  have  been  put  out. 

There  are  various  ways  of  fighting  fires,  depending  on 
the  character  of  the  fire, — whether  it  is  a  surface  fire,  burning 
along  the  surface  layer  of  dry  leaves  and  small  ground 
vegetation,  a  ground  fire,  burning  below  the  surface,  through 
the  layer  of  soil  and  vegetable  matter  that  generally  lines 
the  forest  floor,  or  a  top  fire,  burning  high  up  in  the  trees. 

When  the  fire  runs  along  the  surface  only,  the  injury 
extends  to  the  butts  of  the  trees  and  to  the  young  seedlings. 
Such  fires  can  be  put  out  by  throwing  dirt  or  sand  over  the 
fire,  by  beating  it,  and,  sometimes,  by  merely  raking  the 
leaves  away. 

Ground  fires  destroy  the  vegetable  mold  which  the  trees 
need  for  their  sustenance.  They  progress  slowly  and  kill 
or  weaken  the  roots  of  the  trees. 

Top  fires,  Fig.  133,  are  the  most  dangerous,  destroying 
everything  in  their  way.  They  generally  develop  from 
surface  fires,  though  sometimes  they  are  started  by  lightning. 
They  are  more  common  in  coniferous  forests,  because  the 
leaves  of  hardwoods  do  not  burn  so  readily.  Checking 
the  progress  of  a  top  fire  is  a  difficult  matter.  Some  fires 
will  travel  as  rapidly  as  five  miles  an  hour,  and  the  heat 
is  terrific.  The  only  salvation  for  the  forest  lies,  in  many 
cases,  in  a  sudden  downpour  of  rain,  a  change  of  wind,  or 
some  barrier  which  the  fire  cannot  pass.  A  barrier  of  this 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       195 

kind  is  often  made  by  starting  another  fire  some  distance 
ahead  of  the  principal  one,  so  that  when  the  two  fires  meet, 
they  will  die  out  for  want  of  fuel.  In  well-kept  forests, 
strips  or  lanes,  free  from  inflammable  material,  are  often 
purposely  made  through  the  forest  area  to  furnish  pro- 


FIG.  133. — A  Top  Fire  near  Bear  Canyon,  Arizona. 

tection  against  top  fires.  Carefully  managed  forests  are 
also  patrolled  during  the  dry  season  so  that  fires  may  be 
detected  and  attacked  in  their  first  stages.  Look-out 
stations,  watch-towers,  telephone-connections  and  signal 
stations  are  other  means  frequently  resorted  to  for  fire 
protection  and  control.  Notices  warning  campers  and 


196 


STUDIES  OF  TREES 


trespassers  against  starting  fires  are  commonly  posted  in 
such  forests.     (Fig.  143.) 

The  grazing  of  sheep,  goats  and  cattle  in  the  forest  is 
another  important  source  of  injury  to  which  foresters  must 
give  attention.  In  the  West  this  is  quite  a  problem,  for, 


FIG.  134. — Sheep  Grazing  on  Holy  Cross  National  Forest,  Colorado. 
The  drove  consists  of  1600  sheep,  of  which  only  part  are  shown  in 
the  photograph. 

when  many  thousands  of  these  animals  pass  through  a 
forest  (Fig.  134),  there  is  often  very  little  young  growth 
left  and  the  future  reproduction  of  the  forest  is  severely 
retarded.  Grazing  on  our  National  Forests  is  regulated 
by  the  Government. 

As  a  means  of  protection  against  insects  and  fungi,  all 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       197 

trees  infested  are  removed  as  soon  as  observed  and  in 
advance  of  all  others,  whenever  a  lumbering  operation  is 
undertaken. 

How  forests  are  harvested:    Forestry  and  forest  pres- 


FIG.  135.— A  Typical  Montana  Sawmill. 

ervation  require  that  a  forest  should  be  cut  and  not  merely 
held  untouched.  But  it  also  demands  that  the  cutting 
shall  be  done  on  scientific  principles,  and  that  only  as  much 
timber  shall  be  removed  in  a  given  time  as  the  forest  can 
produce  in  a  corresponding  period.  After  the  cutting,  the 
forest  must  be  left  in  a  condition  to  produce  another  crop 


198  STUDIES  OF  TREES 

of  timber  within  a  reasonable  time;  see  Fig.  122.  These 
fundamental  requirements  represent  the  difference  between 
conservative  lumbering  and  ordinary  lumbering.  Besides 
insuring  a  future  supply  of  timber,  conservative  lumbering-, 
or  lumbering  on  forestry  principles,  also  tends  to  preserve 
the  forest  floor  and  the  young  trees  growing  on  it,  and 
to  prevent  injury  to  the  remaining  trees  through  fire, 
insects  and  disease.  It  provides  for  a  working  plan  by 
which  the  kind,  number  and  location  of  the  trees  to  be  cut 
are  specified,  the  height  of  the  stumps  is  stipulated  and 
the  utilization  of  the  wood  and  by-products  is  regulated. 

Conservative  lumbering  provides  that  the  trees  shall 
be  cut  as  near  to  the  ground  as  possible  and  that  they  shall 
be  felled  with  the  least  damage  to  the  young  trees  growing 
near  by.  The  branches  of  the  trees,  after  they  have  been 
felled,  must  be  cut  and  piled  in  heaps,  as  shown  in  Fig.  122, 
to  prevent  fire.  When  the  trunks,  sawed  into  logs,  are 
dragged  through  the  woods,  care  is  taken  not  to  break 
down  the  young  trees  or  to  injure  the  bark  of  standing  trees. 
Waste  in  the  process  of  manufacture  is  provided  against, 
uses  are  found  for  the  material  ordinarily  rejected,  and  the 
best  methods  of  handling  and  drying  lumber  are  employed. 
Fig.  135  shows  a  typical  sawmill  capable  of  providing 
lumber  in  large  quantities. 

In  the  utilization  of  the  by-products  of  the  forest,  such 
as  turpentine  and  resin,  Forestry  has  devised  numerous 
methods  for  harvesting  the  crops  with  greater  economy 
and  with  least  waste  and  injury  to  the  trees  from  which  the 
by-products  are  obtained.  Fig.  136  illustrates  an  improved 
method  by  which  crude  turpentine  is  obtained. 

Forestry  here  and  abroad:  Forestry  is  practiced  in 
every  civilized  country  except  China  and  Turkey.  In 
Germany,  Forestry  has  attained,  through  a  long  series  of 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       199 


FIG.  136.— Gathering  Crude  Turpentine  by  the  Cup  and  Gutter 
Method.  This  system,  devised  by  foresters,  saves  the  trees  and 
increases  the  output. 

years,  a  remarkable  state  of  scientific  thoroughness  and 
has  greatly  increased  the  annual  output  of  the  forests  of  that 
country. 

In    France,    Switzerland,    Austria,    Hungary,    Norway, 


200  STUDIES  OF  TREES 

Sweden,  Russia  and  Denmark,  Forestry  is  also  practiced 
on  scientific  principles  and  the  government  in  each  of  these 
countries  holds  large  tracts  of  forests  in  reserve.  In  British 
India  one  finds  a  highly  efficient  Forest  Service  and  in 
Japan  Forestry  is  receiving  considerable  attention. 

In  the  United  States,  the  forest  areas  are  controlled 
by  private  interests,  by  the  Government  and  by  the  States. 
On  privately  owned  forests,  Forestry  is  practiced  only  in 
isolated  cases.  The  States  are  taking  hold  of  the  problem 
very  actively  and  in  many  of  them  we  now  find  special 
Forestry  Commissions  authorized  to  care  for  vast  areas 
of  forest  land  reserved  for  State  control.  These  Com- 
missions employ  technically  trained  foresters  who  not  only 
protect  the  State  forests,  but  also  plant  new  areas,  encourage 
forest  planting  on  private  lands  and  disseminate  forestry 
informtiaon  among  the  citizens.  New  York  State  has 
such  a  Commission  that  cares  for  more  than  a  million  acres 
of  forest  land  located  in  the  northern  part  of  the  State. 
Many  other  States  are  equally  progressive. 

The  United  States  Government  is  the  most  active  factor 
in  the  preservation  of  our  forests.  The  Government  to-day 
owns  over  two  hundred  million  acres  of  forest  land,  set 
aside  as  National  Forests.  There  are  one  hundred  and 
fifty  individual  reserves,  distributed  as  shown  in  Fig.  137 
and  cared  for  by  the  Forest  Service,  a  bureau  in  the  Depart- 
ment of  Agriculture.  Each  of  the  forests  is  in  charge  of  a 
supervisor.  He  has  with  him  a  professional  forester  and  a 
body  of  men  wrho  patrol  the  tract  against  fire  and  the  illegal 
cutting  of  timber.  Some  of  the  men  are  engaged  in  planting 
trees  on  the  open  areas  and  others  in  studying  the  important 
forest  problems  of  the  region.  Fig.  138. 

Where  cutting  is  to  be  done  on  a  National  Forest,  the 
conditions  are  investigated  by  a  technically  trained  forester 


WHAT  FORESTRY  IS  AND  WHAT  IT  DOES       201 


202 


STUDIES  OF  TREES 


and  the  cutting  is  regulated  according  to  his  findings. 
Special  attention  is  given  to  discovering  new  uses  for  species 
of  trees  which  have  hitherto  been  considered  valueless, 


FIG.  138. — Government  Foresters  in  Missouri  Studying  the  Growth 
and  Habits  of  Trees.     They  are  standing  in  water  three  feet  deep. 

and  the  demand  upon  certain  rare  species  is  lessened  by 
introducing  more  common  woods  which  are  suitable  for 
use  in  their  place. 

Aside  from  the  perpetuation  of  the  national  forests. 


CARE  OF  THE  WOODLAND  203 

the  U.  S.  Forest  Service  also  undertakes  such  tree  studies 
as  lie  beyond  the  power  or  means  of  private  individuals. 
It  thus  stands  ready  to  cooperate  with  all  who  need  assistance. 


STUDY  II.     CARE   OF  THE   WOODLAND 

Almost  every  farm,  large  private  estate  or  park  has  a 
wooded  area  for  the  purpose  of  supplying  fuel  or  for 
enhancing  the  landscape  effect  of  the  place.  In  most 
instances  these  wooded  areas  are  entirely  neglected  or  are  so 
improperly  cared  for  as  to  cause  injury  rather  than  good. 
In  but  very  few  cases  is  provision  made  for  a  future  growth 
of  trees  after  the  present  stock  has  gone.  Proper  attention 
will  increase  and  perpetuate  a  crop  of  good  trees  just  as 
it  will  any  other  crop  on  the  farm,  while  the  attractiveness 
of  the  place  may  be  greatly  enhanced  through  the  intelligent 
planting  and  care  of  trees. 

How  to  judge  the  conditions:  A  close  examination  of 
the  wooded  area  may  reveal  some  or  all  of  the  following 
unfavorable  conditions : 

The  trees  may  be  so  crowded  that  none  can  grow  well. 
A  few  may  have  grown  to  large  size  but  the  rest  usually 
are  decrepit,  and  overtopped  by  the  larger  trees.  They 
are,  therefore,  unable,  for  the  want  of  light  and  space,  to 
develop  into  good  trees.  Fig.  139  shows  woodland  in 
such  condition. 

There  may  also  be  dead  and  dying  trees,  trees  infested 
with  injurious  insects  and  fungi  and  having  any  number 
of  decayed  branches.  The  trees  may  be  growing  so  far 
apart  that  their  trunks  will  be  covered  with  suckers  as  far 
down  as  the  ground,  or  there  may  be  large,  open  gaps  with 
no  trees  at  all.  Here  the  sun,  striking  with  full  force,  may 


204 


STUDIES  OF  TREES 


FIG.  139. — Woodland  which  Needs  Attention.      The  trees  are 
overcrowded. 


CARE  OF  THE  WOODLAND 


205 


be  drying  up  the  soil  and  preventing  the  decomposition  of 
the  leaves.     Grass  soon  starts  to  grow  in  these  open  spaces 


FIG.  140. — First  Stage  of  Deterioration.     The  woodland  is  too  open 
and  grass  has  taken  the  place  of  the  humus  cover. 

and  the  whole  character  of  the  woodland  changes  as  shown 
in  Figs.  140  and  141. 

Where    any    of    these    conditions  exist,   the  woodland 


206 


STUDIES  OF  TREES 


requires  immediate  attention.  Otherwise,  as  time  goes  on, 
it  deteriorates  more  and  more,  the  struggle  for  space  among 
the  crowded  and  suppressed  trees  becomes  more  keen, 
the  insects  in  the  dying  trees  multiply  and  disease  spreads 
from  tree  to  tree.  Under  such  conditions,  the  soil  deteri- 
orates and  the  older  trees  begin  to  suffer. 


FIG.  141. — Second  Stage  of  Deterioration.     The  Surface  Soil  of  the 
Wooded  Area  Has  Washed  Away  'and  the  Trees  Have  Died. 

The  attention  required  for  the  proper  care  of  woodland 
may  be  summed  up  under  the  four  general  heads  of  soil 
preservation,  planting,  cutting,  and  protection. 

Improvement  by  soil  preservation :  The  soil  in  a  wooded 
area  can  best  be  preserved  and  kept  rich  by  doing  two 


CARE  OF  THE  WOODLAND  207 

things;  by  retaining  the  fallen  leaves  on  the  ground  and  by 
keeping  the  ground  well  covered  with  a  heavy  growth  of 
trees,  shrubs  and  herbaceous  plants.  The  fallen  leaves 
decompose,  mix  with  the  soil  and  form  a  dark-colored 
material  known  as  humus.  The  humus  supplies  the  tree 
with  a  considerable  portion  of  its  food  and  helps  to  absorb 
and  retain  the  moisture  in  the  soil  upon  which  the  tree  is 
greatly  dependent.  A  heavy  growth  of  trees  and  shrubs 
has  a  similar  effect  by  serving  to  retain  the  moisture  in  the 
soil. 

Improvement  by  planting:  The  planting  of  new  trees 
is  a  necessity  on  almost  any  wooded  area.  For  even  where 
the  existing  trees  are  in  good  condition,  they  cannot  last 
forever,  and  provision  must  be  made  for  others  to  take  their 
place  after  they  are  gone.  The  majority  of  the  wooded 
areas  in  our  parks  and  on  private  estates  are  not  provided 
with  a  sufficient  undergrowth  of  desirable  trees  to  take  the 
place  of  the  older  ones.  Thus,  also,  the  open  gaps  must 
be  planted  to  prevent  the  soil  from  deteriorating. 

Waste   lands   on  farms   which   are   unsuited   for   farm 
crops    often    offer    areas    on    which    trees    may    profitably 
be   planted.     These   lands   are   sufficiently    good   in   most 
cases   to   grow   trees,  thus   affording  a  means    of   turning 
into   value   ground  which  would   otherwise   be   worthless. 
It    has   been   demonstrated    that   the    returns   from  such 
plantations  at  the  end  of  fifty  years  will  yield  a  six  per  cent 
investment  and  an  extra  profit  of  $151.97  per  acre,  the 
expense  totaling  at  the  end  of  fifty  years,  $307.03.     The 
value  of  the  land  is  estimated  at  $4  per  acre  and  the  cost  of 
the  trees  and  planting  at  $7  per  acre.     The  species  figured 
on  here  is  white  pine,  one  of  the  best  trees  to  plant  from  a 
commercial    standpoint.     With    other    trees,    the    returns 
will  vary  accordingly. 


208 


STUDIES  OF  TREES 


The  usual  idea  that  it  costs  a  great  deal  to  plant  several 
thousand  young  trees  is  erroneous.  An  ordinary  woodlot 
may  be  stocked  with  a  well-selected  number  of  young  trees 
at  a  cost  less  than  the  price  generally  paid  for  a  dozen  good 
specimen  trees  for  the  front  lawn.  It  is  not  necessary  to 


FIG.  142.— A  Farm  Woodlot. 


underplant  the  woodlot  with  big  trees.  The  existing  big 
trees  are  there  to  give  character  to  the  forest  and  the  new 
planting  should  be  done  principally  as  a  future  investment 
and  as  a  means  of  perpetuating  the  life  of  the  woodlot. 
Young  trees  are  even  more  desirable  for  such  planting 
than  the  older  and  more  expensive  ones.  The  young  trees 
will  adapt  themselves  to  the  local  soil  and  climatic  con- 


CARE  OF  THE  WOODLAND  209 

ditions  more  easily  than  the  older  ones.  Their  demand  for 
food  and  moisture  is  more  easily  satisfied,  and  because  of 
their  small  cost,  one  can  even  afford  to  lose  a  large  per- 
centage of  them  after  planting. 

The  young  plants  should  be  two-year-old  seedlings  or 
three-year-old  "  transplants." 

Two-year-old  seedlings  are  trees  that  have  been  grown 
from  the  seed  in  seed  beds  until  they  reach  that  age.  They 
run  from  two  to  fifteen  inches  in  height,  depending  upon 
the  species. 

Three-year-old  "  transplants  "  have  been  grown  from 
the  seed  in  seed  beds  and  at  the  end  of  the  first  or  second 
year  have  been  taken  up  and  transplanted  into  rows,  where 
they  grow  a  year  or  two  longer.  They  are  usually  a  little 
taller  than  the  two-year-old  seedlings,  are  much  stockier 
and  have  a  better  root  system.  For  this  reason,  three-year- 
old  transplants  are  a  little  more  desirable  as  stock  for 
planting.  They  will  withstand  drought  better  than  seedlings. 

The  best  results  from  woodland  planting  are  obtained 
with  native-grown  material.  Such  stock  is  stronger, 
hardier  and  better  acclimated.  Foreign-grown  stock  is 
usually  a  little  cheaper,  owing  to  the  fact  that  it  has  been 
grown  abroad,  under  cheap  labor  conditions. 

The  trees  may  be  purchased  from  reputable  dealers, 
of  whom  there  are  many  in  this  country.  These  dealers 
specialize  in  growing  young  trees  and  selling  them  at  the 
low  cost  of  three  to  ten  dollars  per  thousand.  In  States 
in  which  a  Forestry  Commission  has  been  inaugurated, 
there  have  also  been  established  State  nurseries  where 
millions  of  little  trees  are  grown  for  reforestation  purposes. 
In  order  to  encourage  private  tree  planting,  the  Forestry 
Commissions  are  usually  willing  to  sell  some  of  these  trees 
at  cost  price,  under  certain  conditions,  to  private  land 


210  STUDIES  OF  TREES 

owners.  Inquiries  should  be  made  to  the  State  Forestry 
Commission. 

Great  care  must  be  taken  to  select  the  species  most 
suitable  for  the  particular  soil,  climatic  and  light  conditions 
of  the  woodlot.  The  trees  which  are  native  to  the  locality 
and  are  found  growing  thriftily  on  the  woodlot,  are  the 
ones  that  have  proven  their  adaptability  to  the  local  con- 
ditions and  should  therefore  be  the  principal  species  used 
for  underplanting.  A  list  from  which  to  select  the  main 
stock  would,  therefore,  vary  with  the  locality.  In  the 
Eastern  States  it  would  comprise  the  usual  hardy  trees 
like  the  red,  pin  and  scarlet  oaks,  the  beech,  the  red  and 
sugar  maples,  the  white  ash,  the  tulip  tree,  sycamore,  sweet 
gum  and  locust  among  the  deciduous  trees;  the  white, 
Austrian,  red,  pitch  and  Scotch  pines,  the  hemlock  and  the 
yew  among  the  conifers. 

With  the  main  stock  wTell  selected,  one  may  add  a  num- 
ber of  trees  and  shrubs  that  will  give  to  the  woodland  scene 
a  pleasing  appearance  at  all  seasons.  The  brilliant  autumnal 
tints  of  the  sassafras,  pepperidge,  blue  beech,  viburnum, 
juneberry  and  sumach  are  strikingly  attractive.  The 
flowering  dogwood  along  the  drives  and  paths  will  add  a 
charm  in  June  as  well  as  in  autumn  and  an  occasional  group 
of  white  birch  will  have  the  same  effect  if  planted  among 
groups  of  evergreens.  Additional  undergrowth  of  native 
woodland  shrubs,  such  as  New  Jersey  tea,  red-berried  elder 
and  blueberry  for  the  Eastern  States,  will  augment  the 
naturalness  of  the  scene  and  help  to  conserve  the  moisture 
in  the  soil. 

Two  or  three  years'  growth  will  raise  these  plants  above 
all  grass  and  low  vegetation,  and  a  sprinkling  of  laurel, 
rhododendron,  hardy  ferns  and  a  few  intermingling  colonies 
of  native  wild  flowers  such  as  bloodroot,  false  Solomon's  seal 


CARE  OF  THE  WOODLAND  211 

and  columbines  for  the  East,   as  a  ground  cover  will  put 
the  finishing  touches  to  the  forest  scene. 

As  to  methods  of  planting  the  little  trees,  the  following 
suggestions  may  prove  of  value.  As  soon  as  the  plants 
are  received,  they  should  be  taken  from  the  box  and  dipped 
in  a  thick  puddle  of  water  and  loam.  The  roots  must  be 
thoroughly  covered  with  the  mud.  Then  the  bundles 
into  which  the  little  trees  are  tied  should  be  loosened  and 
the  trees  placed  in  a  trench  dug  on  a  slant.  The  dirt  should 
be  placed  over  the  roots  and  the  exposed  parts  of  the  plants 
covered  with  brush  or  burlap  to  keep  away  the  rays  of  the  sun. 

When  ready  for  planting,  a  few  plants  are  dug  up,  set  in 
a  pail  with  thin  mud  at  the  bottom  and  carried  to  the  place 
of  planting.  The  most  economical  method  of  planting 
is  for  one  man  to  make  the  holes  with  a  mattock.  These 
holes  are  made  about  a  foot  -in  diameter,  by  scraping  off 
the  sod  with  the  mattock  and  then  digging  a  little  hole  in 
the  dirt  underneath.  A  second  man  follows  with  a  pail 
of  plants  and  sets  a  single  plant  in  this  hole  with  his  hands, 
see  Fig.  129,  making  sure  that  the  roots  are  straight  and 
spread  out  on  the  bottom  of  the  hole.  The  dirt  should 
then  be  packed  firmly  around  the  plant  and  pressed  down 
with  the  foot. 

Improvement  by  cutting:  The  removal  of  certain  trees 
in  a  grove  is  often  necessary  to  improve  the  quality  of  the 
better  trees,  increase  their  growth,  make  the  place  accessible, 
and  enhance  its  beauty.  Cutting  in  a  wooded  area  should 
be  confined  to  suppressed  trees,  dead  and  dying  trees  and 
trees  badly  infested  with  insects  and  disease.  In  case  of 
farm  woodlands,  mature  trees  of  market  value  may  be  cut, 
but  in  parks  and  on  private  estates  these  have  a  greater 
value  when  left  standing.  The  cutting  should  leave  a 
clean  stand  of  well-selected  specimens  which  will  thrive 


212  STUDIES  OF  TREES 

under  the  favorable  influence  of  more  light  and  growing 
space.  Considerable  care  is  required  to  prevent  injury 
to  the  young  trees  when  the  older  specimens  are  cut  and 
hauled  out  of  the  woods.  The  marking  of  the  trees  to  be 
removed  can  best  be  done  in  summer  when  the  dead  and 
live  trees  can  be  distinguished  with  ease  and  when  the 
requisite  growing  space  for  each  tree  can  be  judged  better 
from  the  density  of  the  crowns.  The  cutting,  however, 
can  be  done  most  advantageously  in  winter. 

Immediately  after  cutting  all  diseased  and  infested 
wood  should  be  destroyed.  The  sound  wood  may  be 
utilized  for  various  purposes.  The  bigger  logs  may  be 
sold  to  the  local  lumber  dealers  and  the  smaller  material 
may  be  used  for  firewood.  The  remaining  brush  should  be 
withdrawn  from  the  woodlot  to  prevent  fire  during  the  dry 
summer  months. 

In  marking  trees  for  removal,  a  number  of  considerations 
are  to  be  borne  in  mind  besides  the  elimination  of  dead, 
diseased  and  suppressed  trees.  When  the  marker  is  work- 
ing among  crowding  trees  of  equal  height,  he  should  save 
those  that  are  most  likely  to  grow  into  fine  specimen  trees 
and  cut  out  all  those  that  interfere  with  them.  The 
selection  must  also  favor  trees  which  are  best  adapted 
to  the  local  soil  and  climatic  conditions  and  those  which 
will  add  to  the  beauty  of  the  place.  In  this  respect  the 
method  of  marking  will  be  different  from  that  used  in 
commercial  forestry,  where  the  aim  is  to  net  the  greatest 
profit  from  the  timber.  In  pure  forestry  practice,  one 
sees  no  value  in  such  species  as  dogwood,  iron  wood,  june- 
berry,  sumac  and  sassafras,  and  will  therefore  never  allow 
those  to  grow  up  in  abundance  and  crowd  out  other  trees 
of  a  higher  market  value.  But  on  private  estates  and  in 
park  woodlands  where  beauty  is  an  important  consideration, 


CARE  OF  THE  WOODLAND  213 

such  species  add  wonderful  color  and  attractiveness  to  the 
forest  scene,  especially  along  the  roads  and  paths,  and 
should  be  favored  as  much  as  the  other  hardier  trees.  One 
must  not  mark  too  severely  in  one  spot  or  the  soil  will  be 
dried  out  from  exposure  to  sun  and  wind.  When  the  gaps 
between  the  trees  are  too  large,  the  trees  will  grow  more 
slowly  and  the  trunks  will  become  covered  with  numerous 
shoots  or  suckers  which  deprive  the  crowns  of  their  necessary 
food  and  cause  them  to  "die  back."  Where  the  trees  are 
tall  and  slim  or  on  short  and  steep  hillsides,  it  is  also 
important  to  be  conservative  in  marking  in  order  that  the 
stand  may  not  be  exposed  to  the  dangers  of  windfall.  No 
hard-and-fast  rule  can  be  laid  down  as  to  what  would 
constitute  a  conservative  percentage  of  trees  to  cut  down. 
This  depends  entirely  on  the  local  conditions  and  on  the 
exposure  of  the  woodlot.  But  in  general  it  is  not  well  to 
remove  more  than  twenty  per  cent  of  the  stand  nor  to 
repeat  the  cutting  on  the  same  spot  oftener  than  once  in 
five  or  six  years.  The  first  cutting  will,  of  course,  be  the 
heaviest  and  all  subsequent  cuttings  will  become  lighter 
and  lighter  until  the  woodlot  is  put  in  good  growing  con- 
dition. On  private  estates  and  parks,  where  beauty  is  the 
chief  aim,  the  woodland  should  be  kept  as  natural,  informal 
and  as  thick  as  possible.  Where  ihe  woodland  is  cut  up 
by  many  paths  and  drives,  density  of  veg  tation  will  add 
to  the  impression  of  depth  and  distance. 

Protection.  This  subject  has  already  been  discussed 
considera1  ly  in  the  previous  study  on  Forestry,  and  here 
it  becomes  necessary  merely  to  add  a  few  suggestions  with 
special  reference  to  private  and  park  woodlands. 

Guarding  woodlands  from  fire  is  the  most  important 
form  of  protection.  Surface  fires  are  very  common  on  small 
woodland  holdings  and  the  damage  done  to  the  standing 


214  STUDIES  OF  TREES 

vegetation  is  generally  underestimated.  An  ordinary  ground 
or  surface  fire  on  a  woodland  area  will  burn  up  the  leaf- 
litter  and  vegetable  mold,  upon  which  the  trees  depend 
so  much  for  food  and  moisture,  and  will  destroy  the  young 
seedlings  on  the  ground  Where  the  fire  is  a  little  more 
severe,  the  older  trees  are  badly  wounded  and  weakened 
and  the  younger  trees  are  frequently  killed  outright.  Insects 
and  disease  find  these  trees  an  easy  prey,  and  all  related 
forest  conditions  commence  to  deteriorate. 

Constant  watchfulness  and  readiness  to  meet  any  emer- 
gency are  the  keynote  of  effective  fire  protection.  Notices 
similar  to  the  one  shown  in  Fig.  143  often  help  to  prevent 
fires.  It  is  also  helpful  to  institute  strict  rules  against 
dropping  lighted  matches  or  tobacco,  or  burning  brush 
when  the  ground  is  very  dry,  or  leaving  smouldering  wood 
without  waiting  to  see  that  the  fire  is  completely  out.  Ther3 
should  be  many  roads  and  foot-paths  winding  through  the 
woodland  in  order  that  they  may  serve  as  checks  or  "  fire 
lanes  "  in  time  of  fire.  These  roads  and  paths  should  be 
kept  free  from  brush  and  leaves  and  should  be  frequently 
patrolled.  When  made  not  too  wide,  unpretentious  and 
in  conformity  with  the  natural  surroundings,  such  drives 
and  paths  can  become  a  very  interesting  feature  of  the 
place,  winding  through  the  woodland,  exposing  its  charms 
and  affording  opportunity  for  pleasant  driving  and  walking. 
The  borders  of  the  paths  can  be  given  special  attention  by 
placing  the  more  beautiful  native  shrubs  in  prominent 
positions  where  they  can  lend  increased  attractiveness. 

In  case  of  fire,  it  should  be  possible  to  call  for  aid  by 
telephone  directly  from  the  woodland  and  to  find  within 
easy  reach  the  tools  necessary  to  combat  fire.  It  is  also 
important  to  obtain  the  co-operation  of  one's  neighbors 
in  protecting  the  adjoining  woodlands,  because  the  dangers 


CARE  OF  THE  WOODLAND  215 


CAUTION! 

Please  help  to  prevent  fire 
and  the  destruction  of  plants  and 
animals  in  these  woods  by  obser- 
ving the  following: 

1.  DO  NOT  Drop  Burning'  Matches  or  Tobacco. 

2.  DO  NOT  Start  a  Fire  for  any  Purpose. 

3.  DO  NOT  Injure  the  Trees  or  Shrubs. 
4-  DO  NOT  Shoot. 

A  Violation  of  the  Above  is  a  Violation  of  the  Law. 


ATTENZIQNE! 

Siete  pregati  di  aiutare  a  prevenire  gl'incendi  e  la  distru- 
zione  di  piante  ed  animali  in  questi  boschi,  osservando  le  seguenti 
precauzioni: 

1.  NON  gettate  fiammiferi  o  sigari  accesi. 

2.  NON  accendete  fuochi  per  ragione  alcuna. 

3.  NON  rovinate  gli  alberi  od  i  germogli. 

4.  NON  sparate. 

La  violazione  di  quanto  sopra  e'  violazione  della  legge. 


OSTRZEZENIE! 

pomagac  ochronie  przed  ogniem  i  zniszczeniem  roslin 
zwierzat    w    tym    lesie    przez    stosowanie   si?   do  nastcpujacych 

1.  N1E  wynucac  zarzacych  •*  zapaJek  lub  tytonhi. 

2.  NIE  rozniecac  ognia  pod  zadnym  w&runkiem. 

3.  NIE  luzkadzac  dnew  ani  krzakow. 
4  NIErtnelac. 

Przekroczenae   powyzszych   praepisow   stanowi   naruszenie   ustawy. 


FIG.  143.— Poster  Suitable  for  Private  Woodlands  and  Forest  Parks. 
The  translations  in  Italian  and  Polish  have  been  used  by  the  writer 
in  this  particular  instance  to  meet  the  local  needs. 


216  STUDIES  OF  TREES 

from  insects,  disease  and  fire  threatening  one  bit  of  wood- 
land area  are  more  or  less  dependent  upon  the  conditions 
in  the  adjoining  woodland. 

As  to  other  forms  of  protection,  passing  mention  may  be 
made  of  the  importance  of  keeping  out  cattle,  sheep  and  hogs 
from  the  woods,  of  eliminating  all  insects  and  disease,  of 
keeping  the  ground  free  from  brush  and  other  inflammable 
material,  of  retaining  on  the  ground  all  fallen  leaves  and 
keeping  the  forest  well  stocked  with  little  trees  and  shrubs. 

Forest  lands  may  be  exempted  from  taxation:  In 
New  York  and  other  States  there  exists  a  State  law  pro- 
viding for  exemption  or  reduction  in  taxes  upon  lands 
which  are  planted  with  forest  trees  or  maintained  as  wooded 
areas.  The  object  of  the  law  is  to  encourage  home  forestry 
and  to  establish  fairness  in  the  agricultural  land-tax  law 
by  placing  forest  lands  in  the  same  category  with  other 
crop-producing  lands.  For  detailed  information  and  a 
copy  of  the  law,  one  should  address  the  local  State  Forestry 
Commission. 


CHAPTER  VIII 

OUR  COMMON  WOODS:    THEIR  IDENTIFICATION, 
PROPERTIES  AND  USES 

WOODS  have  different  values  for  various  practical  pur- 
poses because  of  their  peculiarities  in  structure.  A  knowl- 
edge of  the  structural  parts  of  wood  is  therefore  necessary 
as  a  means  of  recognizing  the  wood  and  of  determining 
why  one  piece  is  stronger,  heavier,  tougher,  or  better 
adapted  for  a  given  service  than  another. 

Structure  of  wood:  If  one  examines  a  cross-section  of 
the  bole  of  a  tree,  he  will  note  that  it  is  composed  of  several 
distinct  parts,  as  shown  in  Fig.  145.  At  the  very  center 
is  a  small  core  of  soft  tissue  known  as  the  pith.  It  is  of 
much  the  same  structure  as  the  pith  of  cornstalk  or  elder, 
with  which  all  are  familiar.  At  the  outside  is  the  bark, 
which  forms  a  protective  covering  over  the  entire  woody 
system.  In  any  but  the  younger  stems,  the  bark  is  com- 
posed of  an  inner,  live  layer,  and  an  outer  or  dead  portion. 

Between  the  pith  at  the  center  and  the  bark  at  the  outside 
is  the  wood.  It  will  be  noted  that  the  portion  next  to  the 
bark  is  white  or  yellowish  in  color.  This  is  the  sapwood.  It- 
is  principally  through  the  sapwood  that  the  water  taken 
in  by  the  roots  is  carried  up  to  the  leaves.  In  some  cases 
the  sapwood  is  very  thin  and  in  others  it  is  very  thi  k, 
depending  partly  on  the  kind  of  tree,  and  partly  on  its 
age  and  vigor.  The  more  leaves  on  a  tree  the  more  sap- 
wood  it  must  have  to  supply  them  with  moisture. 

217 


218 


STUDIES  OF  TREES 


FIG.  144.— Pine  Wood.     (Magnified  30  times.) 


OUR  COMMON  WOODS 


219 


Very  young  trees  are  all  sapwood,  but,  as  they  get  older, 
part  of  the  wood  is  no  longer  needed  to  carry  sap  and  it 
becomes  heartivood.  Heartwood  is  darker  than  the  sap- 
wood,  sometimes  only  slightly,  but  in  other  instances  it 
may  vary  from  a  light-brown  color  to  jet  black.  It  tends  to 


bark 

cambium  layer 
.sapwood 


medullary  rays 
FIG.  145. — Cross-section  of  Oak. 

fill  with  gums,  resins,  pigments  and  other  substances,  but 
otherwise  its  structure  is  the  same  as  that  of  the  sapwood. 
The  wood  of  all  our  common  trees  is  produced  by  a  thin 
layer  of  cells  just  beneath  the  bark,  the  cambium.  The 
cambium  adds  new  wood  on  the  outside  of  that  previously 
formed  and  new  bark  on  the  inside  of  the  old  bark.  A 
tree  grows  most  rapidly  in  the  spring,  and  the  wood  formed 


220 


STUDIES  OF  TREES 


at  that  time  is  much  lighter,  softer  and  more  porous  than 
that  formed  later  in  the  season,  which  is  usually  quite  hard 
and  dense.  These  two  portions,  known  as  early  wood 
or  spring  wood,  and  late  wood  or  summer  wood,  together 
make  up  one  year's  growth  and  are  for  that  reason  called 

annual  rings.  Trees  such 
as  palms  and  yucca  do 
not  grow  in  this  way, 
but  their  wood  is  not 
important  enough  in  this 
country  to  warrant  a 
description. 

If  the  end  of  a  piece 
of  oak  wood  is  examined, 
a  number  of  lines  will 
be  seen  radiating  out 
toward  the  bark  like 
the  spokes  in  a  wheel. 
These  are  the  medullary 
rays.  They  are  present 
in  all  woods,  but  only  in 
a  few  species  are  they 

very   prominent  to  the 

unaided  eye.  Theso  rays 
produce  the  "  flakes  " 
or  "  mirrors  "  that  make 
quartersawed  (radially 

cut)  wood  so  beautiful.  They  are  thin  plates  or  sheets  of 
cells  lying  in  between  the  other  wood  cells.  They  extend 
out  into  the  inner  bark. 

While  much  may  be  seen  with  the  unaided  eye,  better 
results  can  be  secured  by  the  use  of  a  good  magnifying 
flass.  The  end  of  the  wood  should  be  smoothed  off  with  a 


FIG.  146.— White  Oak  Wood. 
(Magnified  20  times.) 


OUR  COMMON  WOODS 


221 


very  sharp  knife;  a  dull  one  will  tear  and  break  the  cells 
so  that  the  structure  becomes  obscured.  With  any  good 
hand  lens  a  great  many  details  will  then  appear  which 
before  were  not  visible.  In  the  case  of  some  woods  like  oak, 
ash,  and  chestnut,  it  will  be  found  that  the  early  wood 
contains  many  compara- 
tively large  openings, 
called  pores,  as  shown 
in  Figs.  146  and  147. 
Pores  are  cross-sections 
of  vessels  which  are  little 
tube-like  elements  run- 
ning throughout  the  tree. 
The  vessels  are  water 
A  wood  with 


carriers. 

its  large  pores  collected 
into  one  row  or  in  a 
single  band  is  said  to  be 
ring-porous.  Fig.  146 
shows  such  an  arrange- 
ment. A  wood  with  its 
pores  scattered  through- 
out the  year's  growth 
instead  of  collected  in  a 
ring  is  diffuse-porous. 
Maple,  as  shown  in  Fig. 
152,  is  of  this  character. 

All  of  our  broadleaf 

woods  are  either  ring-porous  or  diffuse-porous,  though 
some  of  them,  like  the  walnut,  are  nearly  half  way  be- 
tween the  two  groups. 

If  the  wood  of  hickory,  for  example,  be  examined  with 
the  magnifying  lens,  it  will  be  seen  that  there  are  numerous 


FIG.  147.— Example  of  the  Bla?k  Oak 

Group.      (Quercus  coccinea.) 

(Magnified  20  times.) 


222  STUDIES  OF  TREES 

small  pores  in  the  late  wood,  while  running  parallel  with 
the  annual  rings  are  little  white  lines  such  as  are  shown 
in  Fig.  149.  These  are  lines  of  wood  parenchyma.  Wood 
parenchyma  is  found  in  all  woods,  arranged  sometimes  in 
tangential  lines,  sometimes  surrounding  the  pores  and 
sometimes  distributed  over  the  cross-section.  The  dark, 
horn-like  portions  of  hickory  and  oak  are  the  woodfibers. 
They  give  the  strength  to  wood. 

In  many  of  the  diffuse-porous  woods,  the  pores  are  too 
small  to  be  seen  with  the  unaided  eye,  and  in  some  cases 
they  are  not  very  distinct  even  when  viewed  with  a  magni- 
fier. It  is  necessary  to  study  such  examples  closely  in 
order  not  to  confuse  them  with  the  woods  of  conifers. 

The  woods  of  conifers  are  quite  different  in  structure 
from  broadleaf  woods,  though  the  difference  may  not 
always  stand  out  prominently.  Coniferous  woods  have  no 
pores,  their  rays  are  always  narrow  and  inconspicuous, 
and  wood  parenchyma  is  never  prominent.  The  woods 
of  the  pines,  spruces,  larches,  and  Douglas  fir  differ  from 
those  of  the  other  conifers  in  having  resin  ducts,  Fig.  144. 
In  pines  these  are  readily  visible  to  the  naked  eye,  appearing 
as  resinous  dots  on  cross-sections  and  as  pin  scratches 
or  dark  lines  on  longitudinal  surfaces.  The  presence  or 
absence  of  resin  ducts  is  a  very  important  feature  in  identify- 
ing woods,  hence  it  is  very  important  to  make  a  careful 
search  for  them  when  they  are  not  readily  visible. 

How  to  identify  a  specimen  of  wood:  The  first  thing 
to  do  in  identifying  a  piece  of  wood  is  to  cut  a  smooth 
section  at  the  end  and  note  (without  the  magnifier)  the 
color,  the  prominence  of  the  rays  and  pores,  and  any  other 
striking  features.  If  the  pores  are  readily  visible,  the  wood 
is  from  a  broadleaf  tree;  if  the  large  pores  are  collected  in 
a  ring  it  belongs  to  the  ring-porous  division  of  the  broadleaf 


OUR  COMMON  WOODS 


223 


woods.  If  the  rays  are  quite  conspicuous  and  the  wood 
is  hard  and  heavy,  it  is  oak,  as  the  key  given  later  will  show. 
Close  attention  to  the  details  of  the  key  will  enable  one  to 
decide  to  what  group  of  oaks  it  belongs. 

In  most  cases  the  structure  will  not  stand  out  so  promi- 
nently as  in  oak,  so  that  it  is  necessary  to  make  a  careful 
study  with  the  hand  lens.  If  pores  appear,  their  arrange- 
ment, both  in  the  early  wood  and  in  the  late  wood,  should 
be  carefully  noted;  also  whether  the  pores  are  open  or 
rilled  with  a  froth-like  substance  known  as  tyloses.  Wood 


White  Ash 


Black  Ash 


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FIG.  148.— (Magnified  about  8  times.) 


parenchyma  lines  should  be  looked  for,  and  if  present,  the 
arrangement  of  the  lines  should  be  noted. 

If  no  pores  appear  under  the  magnifying  lens,  look 
closely  for  resin  ducts.  If  these  are  found,  note  whether 
they  are  large  or  small,  numerous  or  scattered,  open  or 
closed,  lighter  or  darker  than  the  wood.  Note  also  whether 
the  late  wood  is  very  heavy  and  hard,  showing  a  decided 
contrast  to  the  early  wood,  or  fairly  soft  and  grading  into 
the  early  wood  without  abrupt  change.  Weigh  the  piece 
in  your  hand,  smell  a  fresh-cut  surface  to  detect  the  odor, 
if  any,  and  taste  a  chip  to  see  if  anything  characteristic 
is  discoverable.  Then  turn  to  the  following  key: 


224  STUDIES  OF  TREES 


KEY 

I.    WOODS  WITHOUT  PORES— CONIFERS   OR 
SO-CALLED   "  SOFTWOODS  " 

A.  Woods  with  resin  ducts. 

1.  Pines.    Fig.    144.    Resin    ducts    numerous,    prominent, 
fairly   evenly   distributed.    Wood   often   pitchy.      Resinous 
odor  distinct.     Clear  demarcation  between  heart  and  sapwood. 
There  are  two  groups  of  pines — soft  and  hard. 

(a)  Soft  Pines.  Wood  light,  soft,  not  strong,  even-textured, 
very  easy  to  work.  Change  from  early  wood  to  late  wood 
is  gradual  and  the  difference  in  density  is  not  great. 
(6)  Hard  Pines.  Wood  variable  but  typically  rather  heavy, 
hard  and  strong,  uneven  textured,  fairly  easy  to  work.  Change 
from  early  wood  to  late  wood  is  abrupt  and  the  difference 
in  density  and  color  is  very  marked,  consequently  alternate 
•layers  of  light  and  dark  wood  show.  The  wood  of  nearly 
all  pines  is  very  extensively  employed  in  construction  work 
and  in  general  carpentry. 

2.  Douglas  fir.    Resin  ducts  less  numerous  and  conspicuous 
than   in   the   pines,    irregularly   distributed,    often   in   small 
groups.     Odorless   or   nearly   so.     Heartwood   and   sapwood 
distinct.     The  wood  is  of  two  kinds.     In  one  the  growth 
rings  are  narrow  and  the  wood  is  rather  light  and  soft,  easy 
to  work,  reddish  yellow  in  color;  in  the  other  the  growth 
rings  are  wide,  the  wood  is  rather  hard  to  work,  as  there  is 
great  contrast  between  the  weak  early  wood  and  the  very 
dense  late  wood  of  the  annual  rings. 

Douglas  fir  is  a  tree  of  great  economic  importance  on  the 
Pacific  Coast.  The  wood  is  much  like  hard  pine  both  in  its 
appearance  and  its  uses. 

3.  Spruces.     Resin  ducts  few,  small,  unevenly  distributed; 
appearing  mostly  as  white  dots.     Wood  not  resinous;  odor- 
less.   The  wood  is  white  or  very  light  colored  with  a  silky 
luster  and  with  little  contrast  between  heart  and  sapwood. 
It  is  a  great  deal  like  soft  pine,  though  lighter  in  color  and 
with  much  fewer  and  smaller  resin  ducts. 


OUR  COMMON  WOODS  225 

The  wood  is  used  for  construction,  carpentry,  oars,  sounding 
boards  for  musical  instruments,  and  paper  pulp. 
4.  Tamarack.     Resin  ducts  the  same  as  in  the  spruces.    The 
color  of  the  heartwood  is  yellowish  or  russet  brown;  that  of 
the  distinct  sapwood  much  lighter.     The  wood  is  consider- 
ably like  hard    pine,  but    lacks  the  resinous  odor  and    the 
resin  ducts  are  much  fewer  and  smaller. 
The  wood  is  used  largely  for  cross-ties,  fence  posts,  telegraph 
and  telephone  poles,  and  to  a  limited  extent  for  lumber  in 
general  construction. 

B.     Woods  without  resin  ducts. 

1.  Hemlock.    The  wood   has  a   disagreeable,   rancid   odor, 
is  splintery,   not  resinous,   with   decided   contrast  between 
early  and  late  wood.     Color  light  brown  with  a  slight  tinge 
of  red,  the  heart  little  if  any  darker  than  the  sapwood. 
Hemlock  makes  a  rather  poor  lumber  which  is  used  for  general 
construction,  also  for  cross-ties,  and  pulp. 

2.  Balsam  fir.    Usually  odorless,  not  splintery,  not  resinous, 
with  little   contrast   between  early   and  late   wood.     Color 
white  or  very  light  brown  with  a  pinkish  hue  to  the  late  wood. 
Heartwood  little  if  any  darker  than  the  sapwood.     Closely 
resembles  spruce,  from  which  it  can  be  distinguished  by  its 
absence  of  resin  ducts. 

The  wood  is  used  for  paper  pulp  in  mixture  with  spruce. 
Also  for  general  construction  to  some  extent. 

3.  Cypress.     Odorless  except  in  dark-colored  specimens  which 
are  somewhat  rancid.     Smooth  surface  of  sound  wood  looks 
and  feels  greasy  or  waxy.     Moderate  contrast  between  early 
and  late  wood.     Color  varies  from  straw  color  to  dark  brown, 
often   with   reddish   and   greenish   tinge.     Heartwood   more 
deeply  colored  than  the  sapwood  but  without  distinct  boundary 
line. 

Wood  used  in  general  construction,  especially  in  places  where 
durability  is  required;  also  for  shingles,  cooperage,  posts, 
and  poles. 

4.  Red  Cedar.    Has  a  distinct  aromatic  odor.    Wood  uniform- 
textured;  late  wood  usually  very  thin,  inconspicuous.     Color 
deep  reddish  brown  or  purple,  becoming  dull  upon  exposure; 
numerous  minute  red  dots  often  visible  under  lens.    Sapwood 


226  STUDIES  OF  TREES 

white.    Red  cedar  can  be  distinguished  from  all  the  other 

conifers  mentioned  by  the  deep  color  of  the  wood  and  the 

very  distinct  aromatic  odor. 

Wood  largely  used  for  pencils;  also  for  chests  and  cabinets, 

posts,  and  poles.     It  is  very  durable  in  contact  with  the 

ground. 

Western  red  cedar  is  lighter,  softer,  less  deeply  colored  and  less 

fragrant  than  the  common  Eastern  cedar.     It   grows   along 

the   Pacific    Coast    and    is    extensively    used    for    shingles 

throughout  the  country. 

5.  Redwood.    Wood  odorless  and  tasteless,  uniform-textured, 

light  and  weak,  rather  coarse  and  harsh.     Color  light  cherry. 

Close  inspection  under  lens  of  a  small  split  surface  will  reveal 

many  little  resin  masses  that  appear  as  rows  of  black  or  amber 

beads  which  are  characteristic  of  this  wood. 

Redwood  is  confined  to  portions  of  the  Pacific  Coast.     It  is 

used  for  house  construction,  interior  finish,  tanks  and  flumes, 

shingles,  posts,  and  boxes.     It  is  very  durable. 


II.    WOODS  WITH  PORES— BROADLEAF,  OR  SO-CALLED 
"  HARDWOODS  " 

A,     Ring-porous. 

1.  Woods  uith  a  portion  of  the  rays  very  large  and  conspicuous. 
Oak.  The  wood  of  all  of  the  oaks  is  heavy,  hard,  and 
strong.  They  may  be  separated  into  two  groups.  The 
white  oaks  and  the  red  or  black  oaks, 
(a)  White  oaks.  Pores  in  early  wood  plugged  with  tyloses, 
collected  in  a  few  rows.  Fig.  146.  The  transition  from 
the  large  pores  to  the  small  ones  in  the  late  wood  is  abrupt. 
The  latter  are  very  small,  numerous,  and  appear  as  irregular 
grayish  bands  widening  toward  the  outer  edge  of  the 
annual  ring.  Impossible  usually  to  see  into  the  small  pores 
with  magnifier. 

(6)  Red  or  black  oaks.  Pores  are  usually  open  though 
tyloses  may  occur,  Fig.  147;  the  early  wood  pores  are  in 
several  rows  and  the  transition  to  the  small  ones  in  late 
wood  is  gradual.  The  latter  are  fewer,  larger  and  more 


OUR  COMMON  WOODS  227 

distinct  than  in  white  oak  and  it  is  possible  to  see  into 
them  with  a  hand  lens. 

The  wood  of  the  oaks  is  used  for  all  kinds  of  furniture, 
interior  finish,  cooperage,  vehicles,  cross-ties,  posts,  fuel, 
and  construction  timber. 

2.  Woods  with  none  of  the  rays  large  and  conspicuous, 
(a)  Pores  in  late  wood  small  and  in    radial    lines,  wood 
parenchyma  in  inconspicuous  tangential  lines. 
Chestnut.     Pores  in  early  wood  in  a  broad  band,  oval  in 
shape,  mostly  free  from  tyloses.     Pores  in  late  wood  in 
flame-like   radial   white   patches   that  are   plainly   visible 
without    lens.     Color    medium    brown.     Nearly    odorless 
and   tasteless.     Chestnut   is   readily   separated  from   oak 
by  its  weight  and  absence  of  large  rays;   from  black  ash 
by  the  arrangement  of  the  pores  in  the  late  wood;  from 
sassafras  by  the  arrangement  of  the  pores  in  the  late  wood, 
the  less  conspicuous  rays,  and  the  lack  of  distinct  color. 
The  wood  is  used  for  cross-ties,  telegraph  and  telephone 
poles,  posts,  furniture,  cooperage,  and  tannin  extract.    Dura- 
ble in  contact  with  the  ground. 

(6)  Pores  in  late  wood  small,  not  radially  arranged,  being 
distributed  singly  or  in  groups.  Wood  parenchyma  around 
pores  or  extending  wing-like  from  pores  in  late  wood,  often 
forming  irregular  tangential  lines. 

1.  Ash.  Pores  in  early  wood  in  a  rather  broad  band  (occa- 
sionally narrow),  oval  in  shape,  see  Fig.  148,  tyloses  present. 
Color  brown  to  white,  sometimes  with  reddish  tinge  to 
late  wood.  Odorless  and  tasteless.  There  are  several 
species  of  ash  that  are  classed  as  white  ash  and  one  that 
is  called  black  or  brown  ash. 

(a)  White  ash.    Wood  heavy,  hard,  strong,  mostly   light 
colored  except  in  old  heartwood,  which  is  reddish.     Pores 
in  late  wood,  especially  in  the  outer  part  of  the  annual  ring, 
are  joined  by  lines  of  wood  parenchyma. 
(6)  Black  ash.    Wood  more  porous,  lighter,  softer,  weaker, 
and  darker  colored  than  white  ash.      Pores  in  late  wood 
fewer  and  larger  and  rarely  joined  by  tangential  lines  of 
wood  parenchyma. 
The  wood  of  the  ashes  is  used  for  wagon  and  carriage 


228  STUDIES  OF  TREES 

stock,  agricultural  implements,  oars,  furniture,  interior 
finish,  and  cooperage.  It  is  the  best  wood  for  bent  work. 
2.  Locust.  Pores  in  early  wood  in  a  rather  narrow  band, 
round,  variable  in  size,  densely  filled  with  tyloses.  Color 
varjdng  from  golden  yellow  to  brown,  often  with  greenish 
hue.  Very  thin  sapwood,  white.  Odorless  and  almost 


FIG.  149.— Hickory  Wood.     (Magnified  45  times.) 

tasteless.    Wood  extremely  heavy  and  hard,  cutting  like 
horn.     Locust  bears  little  resemblance  to  ash,  being  harder, 
heavier,  of  a  different  color,  with  more  distinct  rays,  and 
with  the  pores  in  late  wood  in  larger  groups. 
The  wood  is  used  for  posts,  cross-ties,  wagon  hubs,  and 
insulator  pins.      It  is  very  durable  in  contact  with  the 
ground. 
(c)  Pores  in  late  wood  comparatively  large,  not  in  groups 


OUR  COMMON  WOODS 


229 


or  lines.    Wood  parenchyma  in  numerous  fine  but  distinct 

tangential  lines. 

Hickory,  Fig.  149.  Pores  in  early  wood  moderately  large, 
not  abundant,  nearly  round,  filled  with  tyloses.  Color 
brown  to  reddish  brown;  thick  sapwood,  white.  Odorless 
and  tasteless.  Wood  very  heavy,  hard,  and  strong.  Hick- 


FIG.  150.— Elm.    (Magnified  25  times.) 

ory  is  readily  separated  from  ash  by  the  fine  tangential 
lines  of  wood  parenchyma  and  from  oak  by  the  absence  of 
large  rays. 

The  wood  is  largely  used  for  vehicles,  tool  handles,  agricul- 
tural implements,  athletic  goods,  and  fuel. 
(d)  Pores  in  late  wood  small  and  in  conspicuous  wavy  tan- 
gential bands.    Wood  parenchyma  not  in  tangential  lines. 
Elm.    Pores  in  early  wood  not  large  and  mostly  in  a  single 


230  STUDIES  OF  TREES 

row,  Fig.  150  (several  rows  in  slippery  elm),  round,  tyloses 
present.  Color  brown,  often  with  reddish  tinge.  Odorless 
and  tasteless.  Wood  rather  heavy  and  hard,  tough,  often 
difficult  to  split.  The  peculiar  arrangement  of  the  pores  in 
the  late  wood  readily  distinguishes  elm  from  all  other  woods 
except  hackberry,  from  which  it  may  be  told  by  the  fact 
that  in  elm  the  medullary  rays  are  indistinct,  while  they  are 
quite  distinct  in  hackberry;  moreover,  the  color  of  hackberry 
is  yellow  or  grayish  yellow  instead  of  brown  or  reddish 
brown  as  in  elm. 

The  wood  is  used  principally  for  slack  cooperage;  also  for 
hubs,  baskets,  agricultural  implements,  and  fuel. 


Sycamore  Beech  Birch 

FIG.  151. — (Magnified  about  8  times.) 


B.    Diffuse-porous. 

1.  Pores  varying  in  size  from  rather  large  to  minute,  the  largest 
being  in  the  early  wood.    Intermediate  between  ring-porous 
and  diffuse-porous. 

Black  Walnut.  Color  rich  dark  or  chocolate  brown.  Odor 
mild  but  characteristic.  Tasteless  or  nearly  so.  Wood 
parenchyma  in  numerous,  fine  tangential  lines.  Wood 
heavy  and  hard,  moderately  stiff  and  strong. 
The  wood  is  used  principally  for  furniture,  cabinets,  interior 
finish,  moulding,  and  gun  stocks. 

2.  Pores  all  minute  or  indistinct,  evenly  distributed  throughout 
annual  ring. 

(a)  With  conspicuously  broad  rays. 

1.  Sycamore.      Fig.  151.    Rays    practically    all    broad. 
Color  light  brown,  often  with  dark  stripes  or  "  feather 


OUR  COMMON  WOODS  231 

grain."  Wood  of  medium  weight  and  strength,  usually 
cross-grained,  difficult  to  split. 

The  wood  is  used  for  general  construction,  woodenware, 
novelties,  interior  finish,  and  boxes. 

2.  Beech.  With  only  a  part  of  the  rays  broad,  the  others 
very  fine,  Fig.  151.  Color  pale  reddish  brown  to  white; 
uniform.  Wood  heavy,  hard,  strong,  usually  straight- 
grained. 

The  wood  is  used  for  cheap  furniture,  turnery,  cooperage, 
woodenware,  novelties,  cross-ties,  and  fuel.     Much  of  it 
is  distilled. 
(6)  Without  conspicuously  broad  rays. 

1.  Cherry.     Rays  rather  fine  but  very  distinct.     Color  of 
wood    reddish    brown.     Wood    rather    heavy,    hard,  and 
strong. 

The  wood  is  used  for  furniture,  cabinet  work,  moulding, 
interior  finish,  and  miscellaneous  articles. 

2.  Maple,  Fig.  152.    With  part  of  the  rays  rather  broad 
and  conspicuous,  the  others  very  fine.     Color  light  brown 
tinged  with  red.     The  wood  of  the  hard  maple   is  very 
heavy,  hard  and  strong;  that  of  the  soft  maples  is  rather 
light,  fairly  strong.     Maple  most  closely  resembles  birch, 
but  can  be  distinguished  from  it  through  the  fact  that 
in  maple  the  rays  are  considerably  more  conspicuous  than 
in  birch. 

The  wood  is  used  for  slack  cooperage,  flooring,  interior 
finish,  furniture,  musical  instruments,  handles,  and  destruc- 
tive distillation. 

3.  Tulip-tree,  yellow  poplar  or  whitewood.     Rays  all  fine 
but  distinct.     Color  yellow  or  brownish  yellow;  sap  wood 
white.    Wood   light   and   soft,   straight-grained,    easy   to 
work. 

The  wood  is  used  for  boxes,  woodenware,  tops  and  bodies 
of  vehicles,  interior  finish,  furniture,  and  pulp. 

4.  Red  or  sweet  gum.    Rays  all  fine  but  somewhat  less 
distinct  than  in  tulip  tree.     Color  reddish  brown,  often 
with  irregular  dark  streaks  producing  a  "  watered  "  effect 
on  smooth  boards;  thick  sapwood,  grayish  white.     Wood 
rather  heavy,  moderately  hard,  cross-grained,  difficult  to 
work. 


232  STUDIES  OF  TREES 

The  best  grades  of  figured  red  gum  resemble  Circassian 

walnut,  but  the  latter  has  much  larger  pores  unevenly 

distributed  and  is  less  cross-grained  than  red  gum. 

The  wood  is  used  for  finishing,  flooring,  furniture,  veneers, 

slack  cooperage,  boxes,  and  gun  stocks. 

5.  Black  or  sweet  birch,  Fig.  151.    Rays  variable  in  size 


FIG.  152. — Maple.     (Magnified  25  times,) 

but  all  rather  indistinct.     Color  brown,  tinged  with  red, 

often  deep  and  handsome.    Wood  heavy,  hard,  and  strong, 

straight-grained,    readily    worked.     Is    darker    in    color 

and  has  less  prominent  rays  than  maple. 

The  wood  is  used  for  furniture,  cabinet  work,  finishing  and 

distillation. 

6.  Cottonwood.     Rays  extremely  fine  and  scarcely  visible 

even  under  lens.     Color  pale  dull  brown  or  grayish  brown. 


OUR  COMMON  WOODS  233 

Wood  light,  soft,  not  strong,  straight-grained,  fairly  easy 
to  work.  Cottonwood  can  be  separated  from  other  light 
and  soft  woods  by  the  fineness  of  its  rays,  which  is  equaled 
only  by  willow,  which  it  rather  closely  resembles. 
The  wood  is  largely  used  for  boxes,  general  construction, 
lumber,  and  pulp. 

How  to  judge  the  quality  of  wood:  To  know  the  name 
of  a  piece  of  wood  means,  in  a  general  way,  to  know  certain 
qualities  that  are  common  to  all  other  pieces  of  wood  of  that 
species,  but  it  does  not  explain  the  special  peculiarities  of 
the  piece  in  question  or  why  that  particular  piece  is  more 
suitable  or  unsuitable  for  a  particular  purpose  than  another 
piece  of  the  same  species.  The  mere  identification  of  the 
wood  does  not  explain  why  a  particular  piece  is  tougher, 
stronger  or  of  darker  color  than  another  piece  of  the  same 
species  or  even  of  the  same  tree.  The  reason  for  these 
special  differences  lies  in  the  fact  that  wood  is  not  a  homo- 
geneous material  like  metal.  Within  the  same  tree  different 
parts  vary  in  quality.  The  heartwood  is  generally  heavier 
and  of  deeper  color  than  the  sapwood.  The  butt  is  superior 
to  the  top  wood,  and  the  manner  in  which  the  wood  was 
sawed  and  dried  will  affect  its  quality.  Knots,  splits, 
checks,  and  discoloration  due  to  incipient  decay  are  defects 
worth  considering.  Wood  that  looks  lusterless  is  usually 
defective,  because  the  lack  of  luster  is  generally  due  to 
disease.  Woods  that  are  hard  wear  best.  Hardness  can 
be  determined  readity  by  striking  the  wood  with  a  hammer 
and  noting  the  sound  produced.  A  clear,  ringing  sound 
is  a  sign  of  hardness.  The  strength  of  a  piece  of  wood 
can  be  judged  by  its  weight  after  it  is  well  dried.  Heavy 
woods  are  usually  strong.  A  large  amount  of  late  wood 
is  an  indication  of  strength  and  the  production  of  a  clear 
sound  when  struck  with  a  hammer  is  also  an  evidence  of 
strength. 


CHAPTER  IX 

AN  OUTDOOR  LESSON   ON  TREES 

THE  importance  of  nature  study  in  the  training  of  the 
child  is  now  well  recognized.  The  influences  of  such  study 
from  the  hygienic,  moral  and  aesthetic  point  of  view  are 
far  reaching  and  cannot  be  expressed  in  dollars  and  cents. 
In  his  association  with  nature,  the  child  is  led  to  observe 
more  closely  and  to  know  and  to  be  fond  of  what  is  truly 
beautiful  in  life — beautiful  surroundings,  beautiful  thoughts 
and  beautiful  deeds.  He  is  inspired  with  reverence  for 
law,  order  and  truth  because  he  sees  it  constantly  reflected 
in  all  works  of  nature.  The  social  instinct  is  highly  developed 
and  even  the  parents  are  often  bettered  through  the  agency 
of  their  children. 

The  only  way,  however,  to  study  nature — especially 
plants — is  to  study  it  out  of  doors.  Our  present  tendency 
to  gather  in  cities  demands  the  upbuilding  influences  of 
trips  into  the  open  in  order  to  equip  the  child  mentally  and 
physically  to  face  the  world  and  its  work  with  the  strength 
and  tenacity  characteristic  of  the  country-bred.  Moreover, 
the  study  of  objects  rather  than  books  is  an  axiom  in 
modern  education  and  here,  too,  we  can  readily  see  that 
the  best  way  to  study  trees  is  to  take  the  pupil  to  the  trees. 
Such  studies  are  more  lasting  than  book  study  because 
they  emphasize  the  spirit  and  the  goal  rather  than  the 
petty  facts. 

Educators  and  parents  are  now  recognizing  the  value 

234 


AN  OUTDOOR  LESSON  ON  TREES  235 

of  outdoor  trips  for  their  children  and  are  beginning  to 
indulge  in  them  quite  frequently.  In  many  instances 
teachers  about  to  take  out  their  children  for  a  day  have 
inquired  of  the  writer  how  to  go  about  giving  a  general 
field  lesson  when  they  reached  the  park  or  woodland.  The 
purpose  of  this  chapter  is  to  answer  such  a  question  and 
yet  it  is  evident  that  it  cannot  be  answered  completely. 
What  to  observe  out  doors  and  how  to  present  one's  impres- 
sions is  a  broad  question  and  varies  with  the  knowledge 
and  ability  of  the  teacher  as  well  as  with  the  age  and  experi- 
ence of  the  children.  The  how  and  the  what  in  nature 
study  is  of  greater  import  than  the  hard,  dry  facts  and  that 
must  be  left  entirely  to  the  teacher.  A  few  suggestions, 
however,  may  not  be  amiss : 

1.  General  observations  with  a  view  to  character  build- 
ing: First  of  all  it  is  important  to  remember  that  the 
great  value  of  all  tree  and  nature  study  is  the  inculcation 
in  the  minds  of  the  children  of  an  appreciation  and  love 
for  the  beautiful.  Inspiring  them  to  love  trees  generally 
means  more  than  teaching  them  to  know  trees.  Mere 
facts  about  trees  taught  in  an  academic  way  are  often  no 
more  lasting  than  the  formulae  in  trigonometry  which  most 
of  us  have  long  ago  forgotten.  The  important  thing  is 
that  permanent  results  be  left  and  nothing  else  will  produce 
such  lasting  impressions  as  the  study  of  trees  out  of  doors. 

General  observations  about  trees  can  be  made  by 
pointing  out  the  beauty  and  character  of  the  individual 
forms  and  branching,  their  harmony  in  their  relations 
to  each  other  as  factors  of  a  beautiful  composition  and  the 
wealth  of  shades  and  colors  in  their  leaves,  bark  and  flowers. 
Compare,  for  instance,  the  intricate  ramification  of  an 
American  elm  with  the  simple  branching  of  a  sugar  maple, 
the  sturdiness  of  a  white  oak  with  the  tenderness  of  a  soft 


236 


STUDIES  OF  TREES 


maple,  the  wide  spread  of  a  beech  with  the  slender  form 
of  a  Lombardy  poplar,  the  upward  pointing  branches  of  a 


FIG.  153. — Trees  Have  Individuality. 


gingko  with  the  drooping  form  of  a  weeping  willow.     At 
close  range,  each  of  these  trees  reveals  itself  as  an  individual 


AN  OUTDOOR  LESSON  ON  TREES  237 

with  a  character  quite  its  own.  At  little  distance  you 
may  see  them  grouped  together,  subordinating  their  individ- 
uality and  helping  to  blend  into  a  beautiful  composition 
with  a  character  all  its  own.  There  is  nothing  more  inspir- 
ing than  the  variety  of  greens  in  the  spring  foliage,  the 
diversity  of  color  in  the  spring  blossoms  and  the  wonderful 
display  of  autumnal  tints  offered  by  the  sweet  gum,  sassa- 
fras, dogwood,  black  gum,  red  maple,  sugar  maple,  scarlet 
oak,  blue  beech,  sorrel  tree,  ash  and  gingko.  The  white 
bark  of  the  gray  birch,  the  dark  bark  of  the  black  oak, 
the  gray  of  the  beech,  the  golden  yellow  of  the  mulberry 
and  the  mottled  bark  of  the  sycamore  are  interesting  com- 
parisons. The  smooth  bark  of  the  mockernut  hickory 
contrasts  greatly  with  the  shaggy  bark  of  the  shagbark 
hickory— members  of  the  same  family  and  yet  how  different. 
A  wonderful  opportunity  is  thus  offered  for  a  comparative 
study  of  human  nature — individuality  and  community 
life,  all  reflected  in  trees. 

With  this  preliminary  study  and  with  the  addition  of 
some  remarks  on  the  value  of  trees  as  health  givers  and 
moral  uplifters,  the  child  is  interested  and  attracted.  The 
lesson  so  far  has  attained  its  aim. 

2.  Specific  observations  with  a  view  to  training  the 
observative  powers:  The  child's  training  in  closeness  of 
observation  and  scientific  precision  may  be  the  next  con- 
sideration. His  enthusiasm  will  now  prompt  him  to  lend 
his  interest  for  greater  detail.  We  can  teach  him  to  recognize 
a  few  of  the  common  trees  by  their  general  characters— 
an  American  elm  by  its  fan-shaped  form,  a  gray  birch  by 
its  white  bark,  a  white  pine  by  the  five  needles  to  each 
cluster,  a  horsechestnut  by  its  opposite  branching  and  big 
sticky  bud  and  a  willow  by  its  drooping  habit.  After  that 
we  may  introduce,  if  the  age  of  the  pupils  justifies,  more 


238  STUDIES  OF  TREES 

details  extending  to  greater  differences  which  distinguish 
one  species  from  another. 

The  lesson  might  continue  by  pointing  out  the  require- 
ments of  trees  for  water  and  light.  Find  a  tree  on  some 
slope  where  the  roots  are  exposed  and  another  which  is 
being  encroached  upon  by  its  neighbor,  and  show  how  in 
one  case  the  roots  travel  in  search  of  water  and  food  and 
in  the  other  the  branches  bend  toward  the  light,  growing 
more  vigorously  on  that  side.  Compare  the  trees  on  the 
open  lawn  with  those  in  the  grove  and  show  how  those  in 
the  open  have  grown  with  branches  near  the  ground  while 
those  in  the  woodland  are  slender,  tall  and  free  from 
branches  to  some  distance  above  the  ground.  Point  out 
the  lenticels  on  the  bark  of  birch  and  sweet  cherry  trees 
and  explain  how  trees  breathe.  Compare  this  process 
with  that  of  the  human  body.  You  may  now  come  across 
an  old  stump  and  here  you  can  point  out  the  structure  of 
the  wood — the  sapwood,  cambium  and  bark.  You  can 
illustrate  the  annual  rings  and  count  the  age  of  the  tree. 
At  another  point  you  may  find  a  tree  with  a  wround  or 
bruised  bark  and  here  you  can  readily  make  a  closer  study 
of  the  cambium  layer  and  its  manner  of  growth. 

The  adaptation  of  plants  to  the  seasonal  changes  opens 
another  interesting  field  of  study  for  beginners.  If  the 
season  is  the  fall  or  winter,  note  how  the  trees  have  pre- 
pared themselves  for  the  winter's  cold  by  terminating  the 
flow  of  sap,  by  dropping  their  leaves  too  tender  to  resist 
the  winter's  cold,  and  by  covering  their  buds  with  scales 
lined  with  down  on  the  inside.  Observe  how  the  insects 
have  spun  for  themselves  silken  nests  or  remain  preserved 
in  the  egg  state  over  the  winter.  If  the  season  is  spring  or 
summer  the  opposite  may  be  noted.  See  how  everything 
turns  to  life;  how  the  buds  are  opening,  the  leaves 


AN  OUTDOOR  LESSON  ON  TREES  239 

emerging,  the  sap  running,  seeds  germinating  and  flowers 
blooming. 

The  soil  conditions  on  the  lawn  and  in  the  grove  furnish 
another  interesting  feature  of  comparison  and  study.  In 
the  grove,  you  can  demonstrate  the  decomposition  of  the 
fallen  leaves,  the  formation  of  humus  and  its  value  to  the 
tree.  The  importance  of  the  forest  soil  as  a  conservator 
of  water  and  its  relation  to  stream  flow  and  soil  erosion 
can  be  brought  out  at  this  juncture.  An  eroded  bank 
and  a  slope  covered  with  trees  and  shrubs  would  provide 
excellent  models  for  this  study.  A  consideration  of  the 
economic  value  of  the  trees  would  also  be  in  place. 

3.  Civic  lessons  reflected  in  trees:  The  community 
life  of  trees  in  the  grove,  their  growth,  struggles  for  light 
and  food  and  their  mutual  aid  can  be  brought  out  and 
compared  with  the  community  life  among  people.  The 
trees  may  here  be  seen  struggling  with  each  other  for  light 
and  food,  forcing  each  other's  growth  upward,  some  winning 
out  and  developing  into  stalwart  and  thrifty  specimens  and 
others  becoming  suppressed  or  entirely  killed.  On  the  other 
hand  they  may  be  seen  helping  each  other  in  their  com- 
munity growth  by  protecting  each  other  from  windfall  and 
by  contributing  to  the  fertility  of  the  forest  soil  in  drop- 
ping their  leaves  and  shading  the  ground  so  that  these 
fallen  leaves  may  decompose  readily. 

4.  Enemies  of  trees :  An  old  stump  or  tree  may  be  seen 
crumbling  away  under  the  influence  of  fungi  and  here  the 
children  may  be  shown  the  effects  of  tree  diseases  both  as 
destroyers  of  life  and  as  up-builders,  because  fungi  turn 
to  dust  the  living  trees  and  build  up  others  by  furnishing 
them  with  the  decomposed  wood  matter. 

Insects  too,  may  be  invading  the  old  dead  tree,  and 
something  of  their ;  nature,  habits  and  influences  may  be 


240 


STUDIES  OF  TREES 


FIG.  154. — Trees  also  Grow  in  Communities. 

gone  into.  They  may  be  shown  as  wood  borers,  leaf  eaters, 
or  sap  suckers,  all  injurious  to  the  tree.  On  the  other  hand 
they  may  be  shown  as  seed  disseminators  and  as  parasites 
on  other  injurious  insects;  all  benefactors. 


AN  OUTDOOR  LESSON  ON  TREES 


241 


Forest  fires  as  an  enemy  of  trees  might  be  touched  upon 
by  noting  how  easily  the  leaves  may  be  ignited  and  a  sur- 
face fire  started  when  the  season  is  dry.  Top  and  ground  fires 
emanating  from  surface  fires  can  then  be  readily  explained. 

5.  Expression:  The  pupils  have  by  this  time  been 
taught  to  feel  the  beautiful,  to  observe  carefully  and  to 


FIG.  155. — Trees  Blend  Together  to  Form  a  Beautiful  Composition. 


reason  intelligently  and  they  may  now  be  trained  to 
express  themselves  properly.  This  may  be  accomplished 
by  asking  them  to  remember  their  observations  and  to 
write  about  them  in  the  classroom.  The  lesson  may  be 
supplemented  with  effective  reading  about  trees  and 
forests.  Interesting  reading  matter  of  this  sort  can  be 
found  in  abundance  in  children's  readers,  in  special  books 


242  STUDIES  OF  TREES 

on  the  subject  and  in  Arbor  Day  Manuals  published  by 
the  various  State  Education  Departments. 

6.  Preparation:    In    order    to    save   time    looking    for 
objects  of  interest  and  for  the  purpose  of  correlating  the 
various    observations    so   that    all   will   follow    in    orderly 
sequence,  it  is  well  for  the  teacher  or  leader  to  go  over  the 
ground  beforehand  and  note  the  special  features  of  interest 
The  various  topics  can  then  be  given  some  thought  and  a 
brief  synopsis  can  be  drawn  up  to  serve  as  a  memorandum 
and  guide  on  the  trip. 

It  is  also  well  to  be  provided  with  a  hatchet  to  cut 
into  some  decayed  stump,  a  trowel  to  dig  up  the  forest 
soil,  a  knife  for  cutting  off  twigs  and  a  hand  reading  glass 
for  examining  the  structural  parts  of  the  various  objects 
under  observation.  A  camera  is  always  a  valuable  asset 
because  the  photographs  hung  in  the  classroom  become 
records  of  great  interest  to  all  participants. 

7.  Suggestions  for  forming  tree  clubs:    A  good  way  to 
interest   children  in  trees   and  nature   study  is  to  form, 
among    them,    a    Tree    Club.     The    idea    has    been    fully 
developed  in  Brooklyn,  N.  Y.,  Newark,  N.  J.,  and  other 
cities  and  consists  of  forming  clubs  of  children  in  the  public 
schools  and  private  institutions  for  the  purpose  of  interest- 
ing them  in  the  trees  around  their  school  and  their  homes. 
The  members  of  these  clubs  are  each  given  the  tree  warden's 
badge  of  authority  and  assigned  to  some  special  duty  in 
the  preservation  of  the  local  trees.     A  plan  of  study  and  of 
outdoor  trips  is  laid  out  for  them  by  their  director  and  at 
stated  periods  they  are  given  illustrated  lectures  on  trees 
and  taken  to  the  neighboring  parks  or  woodlands. 


INDEX 


Acer  negundo,  45 

—  platanoides,  44,  123 

—  polymorphum,  122 

—  pseudoplatanus,  44 

—  rubrum,  120,  125 

—  saccharinum,  38 

—  saccharum,  37,  121 
vEsculus  hippocastanum,  33,  120 

—  rubicunda,  121 

Ailing  tree,  how  to  tell  an,  153 
Air,  influence  of,  117 
Alternate  branched  trees,  31 
American  beech,  68 

—  elm,  47,  50,  119,  125,  126 

—  larch,  29 

—  linden,  95 
Annual  rings,  186,  220 
Aphides  or  plant  lice,  68,  152 
Apple  rust,  22 

Arbor-vitap  and  red  cedar,  descrip- 
tion of,  19 

—  (northern  white  cedar),  22 
Arsenate  of  lead,  138 

Ash,  wood,  227 
-  black,  35,  227 

—  white,  35,  126 
Ash-leaf  maple,  46 
Aspen,  large-toothed,  54 
— ,  quaking,  54 
Austrian  pine,  9,  11,  122 

Bald  cypress,  30 
Balm  of  Gilead,  54 
Balsam,  fir,  225 
— ,  poplar,  54 


Bark,  106 

Bark,   how  to   prevent   splitting 
when  removing  branches,  162 

—  or  trunk,  trees  told  by  their,  59 
Bass-wood,  98 

Bean,  Indian,  104 
Beech,  American,  68 
— ,  blue,  or  hornbeam,  59,  70 
— ,  copper,  120 
— ,  European,  69 
.—  tree,  59,  128,231 
Beetle,  elm  leaf,  49,  141 
Betula  alba,  68,  120 

—  lutea,  68 
—  lenta,  66 

—  papyrifera,  66 

—  populifolia,  64 
Bhotan  pine,  6,  122 
Bigbud  hickory,  87 
Birch,  black,  66 

— ,  European  white,  68,  120 

—  fungus  rot,  157 
— ,  gray,  64 

— ,  paper,  66 
— ,  sweet,  66 

—  tree,  59 
— ,  white,  64 
— ,  yellow,  68 
Bitternut  hickory,  87 
Black  ash,  35,  227 

—  birch,  66 

—  locust,  100,  126 

—  oak,  75 

—  or  sweet  birch,  232 

—  spruce,  15 

243 


244 


INDEX 


Black  walnut,  87,  230 

Blotches,  leaf,  41 

Blue  beech,  or  hornbeam,  59,  70, 
128 

—  spruce,  123 

Bolting  limbs,  176 

Bordeaux  mixture,  160,  175 

Borer,  bronze-birch,  64 

— ,  hickory  bark,  85,  151 

— ,  linden,  98 

— ,  locust,  100 

— ,  sugar  maple,  37 

Boring  insects,  22,  134 

Box-elder,  45 

Bracing  limbs,  various  methods 
of,  176 

Bracket  fungus,  154 

Branches,  dead  and  broken,  re- 
moval of,  162 

— ,  how  to  prevent  bark  splitting 
when  removing,  162 

Broadleaf  or  "  hardwoods,"  222, 
226 

Bronze-birch  borer,  64 

Brooklyn,  N.  Y.,  242 

Broom  hickory,  87 

Brown  hickory,  87 

Brown-tail  moth,  145 

Buckeye,  34 

Butternut,  83,  90 

Buttonball,  63 

Button  wood,  63 

By-products  of  forests,  utiliza- 
tion of,  198 

Cambium  layer,  106,  109 

Camperdown  elm,  50 

Care   in   selecting   trees  suitable 

for  the  soil,  210 
Carolina  poplar,  51 
Carpinus  caroliniana,  70,  128 
Castanea  dentata,  80 
Catalpa  speciosa,  102 
Caterpillars,  33,  74 


Caterpillars,  leaf-eating,  95 

— ,  spraying  for,  145 

Catkin,  ~66 

Cattle  grazing  in  forests  a  source 
of  injury,  196 

Cavities,  fungous  diseases  attack- 
ing, 172 

—  how  caused,  170 

— ,  manner  of  filling,  172 

Cedar  apple,  22 

— ,  white,  24 

Celtis  occidentalis,  70 

Chamaecyparis  thyoides,  24 

Character  building  and  trees,  235 

Chestnut,  80,  227 

—  and  oaks,  71 

—  disease,  158 
Chewing  insects,  134 
Cherry,  231 

Child  training  in  observation  and 

precision,  237 
Chlorophyll,  109 

Civic  lessons  reflected  in  trees,  239 
Climbing  trees,  precautions,  167 
Clubs,  tree,  242 
Coffee  tree,  120 
Colorado  blue  spruce,  15 
Color  of  leaves,  109 
Common  catalpa,  104 
-  locust,  101 

Community  life  of  trees,  182,  239 
Conifers  or  "  softwoods,"  222,  224 
Coniferous  trees,  122 
Copper  beech,  120 
Cork  elm,  95 

Cornus  florida,  104,  122,  128 
Corrosive  sublimate,  175 
Cottonwood,  51,  232 
Cottony-maple  scale,  39 
Crataegus  oxyacantha,  128 
Crown,  107 
Cucumber  tree,  99 
Cypress,  225 

—  and  larch,  description  of,  25 


INDEX 


245 


Cypress,  bald,  30 

—  knees,  31,  117 

— ,  obtuse  leaf,  Japanese,  123 

Dead  and  broken  branches,  re- 
moval of,  162 

Deciduous  trees,  119 

Destroying  injurious  insects, 
methods  of,  134 

—  pupae,  141 

Developing    disease,    moisture    a 

factor  in,  112 
Diaporthe  parasitica,  82 
Diffuse-porous  woods,  221,  230 
Disease,  fungi  as  factors  of,  155 
— ,  moisture  a  factor  in  develop- 
ing, 112 

Dogwood,  flowering,  104,  122 
Douglas  fir,  224 

Effect  of  heat  on  trees,  116 

Elkwood,  100 

Elm,  229 

— ,  American,  47,  50,  119,  126 

— ,  Camperdown,  50 

— ,  cork,  95 

— ,  English,  50 

—  leaf  beetle,  49,  141 

— ,  poplar,  gingko  and  willow  trees, 
told  by  their  form,  46 

— ,  white,  50 

Enemies  of  trees,  239 

Enemy  of  trees,  forest  fires  as  an 
241 

English  elm,  50 

—  hawthorn,  128 

—  yew,  123 
European  beech,  69 

-  larch,  25,  122,  126 

—  linden,  98,  119 

—  weeping  birch,  121 

—  white  birch,  68,  120 

Fall  webworm,  148 


Fagus,  128 

—  americana,  68 

—  sylvatica,  69,f120 
Fern,  maidenhair,  55 

Fighting  forest  fires,  various  ways 

of,  194 

Filling  cavities,  manner  of,  172 
Fire,   guarding   woodlands  from, 

193,  213,  215 

Flowering  dogwood,  104,  122 
Foliage,  spraying,  141 
Forest  fires  as  an  enemy  of  trees, 

241 
,  various  ways  of  fighting, 

194 

—  lands,  exemption  from  taxa- 

tion, 216 
— ,  life  and  nature  of,  182 

—  trees,  pruning,  166 
Forestry  in  various  countries,  198 
— ,  what  it  is  and  what  it  does,  179 
Forests,     grazing     cattle     in,     a 

source  of  injury,  196 
Forest  Service,  U.  S.,  200 
— ,  harvesting,  196 
— ,    harvesting    of,    to    increase 

production,  180 
— ,  how  established,  190 
— ,  how  harvested,  197 
— ,  how  protected,  193 
— ,   how   they   help   to   regulate 

streams  and  prevent  floods, 

187 

— ,  method  of  establishing,  191 
— ,  planting,  with  seedling  trees, 

189 

—  prevent  soil  erosion,  187 

— ,    protecting   from    destructive 

agencies,  193 
— ,  safeguarding,  179 
— ,  utilization  of  by-products,  198 
Fraxinus  americana,  35,  126 

—  nigra,  35 

Frost,  effect  of,  on  trees,  116 


246 


INDEX 


Fungi    and    insects,     protection 
against,  196 

—  as  factors  of  disease,  155 
Fungous  diseases  attacking  cav- 

*   ities,  172 

—  diseases,  spraying  for,  160 
Fungus,  fruiting  body  of,  156 

Gingko  biloba,  55,  120,  124 

—  or  maidenhair  tree,  55,  120 
Gipsy  moth,  74,  143 
Gleditsia  triacanthos,  102 
Gloeosporium  nervisequum,  62 
Gray  or  white  birch,  64 
Grazing  effect  on  forests,  196 
Grove  and   lawn,   study  of  soil 

conditions  on,  239 
Gum,  red  or  sweet,  95,  231 
Gymnocladus  dioicus,  120 

Hackberry  tree,  59,  70 
Hackmatack,  29 
Hard  maple,  38 
-  pines,  224 
"Hardwoods,"  or  broadleaf  trees, 

226 

Hardy  catalpa,  102 
Harvesting  forests,  196 
Harvesting  of  forests  to  increase 

production,  180 
Hawthorn,  English,  128 
Healthy    tree,    conditions    which 

indicate,  153 
Heartwood,  106,  219 
Heat,  effect  of,  on  trees,  116 
Hemlock,  17,  128,  225 
—  and  spruce,  description  of,  11 
Hickory,  229 

—  bark  borer,  85,  151 
— ,  bigbud,  87 

— ,  bitternut,  87 

— ,  broom,  87 

— ,  brown,  87 

— ,  mockernut,  44,  86 


Hickory,  pignut,  87 
— ,  shagbark,  83 
— ,  shellbark,  85 
— ,  whiteheart,  87 
Hicoria  alba,  86 

—  glabra,  87 

—  minima,  87 
-  ovata,  83 

Honey  locust,  102 
Hop  hornbeam,  70 
Hornbeam,  (blue  beech),  70 
Horsechestnut,  33,  120 
— ,  red,  34,  121 
Humus,  113,  207 
Hydrophytes,  111 

Important  insects,  141 
Improperly  pruned  trees,  161 
Indian  bean,  104 

Individuality  of  trees,  1,  182,  239 
Insects     and     fungi,     protection 

against,  196 
— ,  boring,  22,  134 
— ,  chewing,  134 

—  galls,  71 

— ,  important  kinds  of,  141 

—  injurious  to  trees,  134 
— ,  leaf-eating,  49 

— ,  methods  of  destroying  injuri- 
ous, 134 

— ,  nature,  habits  and  influences 
of,  239 

— ,  sucking,  134 

— ,  the  four  stages,  or  life  his- 
tory of,  140 

Iron  wood  tree,  59,  70 

Italian  or  Lombardy  poplar,  51, 
128 

Japanese  maple,  122 

—  umbrella  pine,  123 
Juglans  cinerea,  GO 

—  nigra,  87 
Juniper,  22 


INDEX 


247 


Juniperus  communis,  22 
Juniperus  virginiana,  19 

Kerosene  emulsion,  139 
Knees,  cypress,  31 

Larch,  American,  29 

—  and  cypress,  description  of,  C5 
-  European,  25,  122,  126 

Large-toothed  aspen,  54 

Larix  europaea,  26,  122,  126 

Lawn  and  grove,  study  of  soil 
conditions  on,  239 

Lawn  trees,  119 

,  pruning,  166 

Leaf  blotches,  41 

Leaf-eating  caterpillars,  95 

,  insect,  49 

Leaves,  107 

— ,  needle-shaped,  19 

— ,  scale-like,  19 

— ,  star-shaped,  93 

Lenticels,  64,  117 

Leopard  moth,  39,  49,  149 

Lesson  on  trees,  outdoor,  234 

Light,  influence  of,  on  trees,  114 

Limbs,  various  methods  of  brac- 
ing, 176 

Lime-sulphur  wash,  139 

Lime-tree,  98 

Linden,  American,  95 

—  borer,  98 

— ,  European,  99,  119 
Liquidambar  styraciflua,  93 
Liriodendron,  tulipifers,  90,   12G, 

231 
Location    of    trees,    care    to    be 

exercised  in,  130 
Locust,  101,  228 
— ,  black,  100,  126 

—  borer,  100 

— ,  common,  101 
— ,  honey,  102 

—  miner,  100 


Locust,  yellow,  101 

Lombard  y  or  Italian  poplar,  51, 

128 
Low  juniper,  22 

Magnolia  acuminata,  99 
— ,  mountain,  99 

—  soulangeana,  121 
— ,  Soulange's,  121 

—  tripetala,  100 
Magnolias,  the,  99 
Maidenhair  fern,  55 

—  or  gingko  tree,  55,  120 

Maple  wood,  231 

— ,  ash-leaf,  46 

— ,  hard,  38 

— ,  Japanese,  122 

— ,  Norway,  44,  123 

—  phenacoccus,  37 
— ,  red,  120,  125 
— ,  rock,  38 

— ,  silver,  38 
— ,  soft,  40 
-  sugar,  37,  121 

—  swamp,  43 
— ,  sycamore,  44 
— ,  white,  40 
Mesophytes,  111 

Method  of  covering  wounds,  164 
Methods  of  destroying  injurious 

insects,  134 

Mockernut  hickory,  44,  86 
Moisture  a  factor  in  developing 

disease,  112 

— ,  influence  of,  on  trees,  110 
Moral  influence  of  trees,  237 
Morus  alba,  105 

—  rubra,  105 
Moth,  gipsy,  74 
— ,  leopard,  39,  49 
Mountain  magnolia,  99 
Mugho  pine,  123 
Mulberry,  red,  105 

— ,  white,  105 


248 


INDEX 


National  forests,  200 

Needle-shaped  leaves,  19 

Nettle  tree,  71 

Newark,  N.  J.,  242 

Northern    white    cedar      (arbor- 

vitae),  22 
Norway  maple,  44,  123 

—  spruce,  13 
Nursery,  tree,  132 

Oak  226 
— ,  black,  75 
— ,  pin,  79,  119,  125 
— ,  red,  76,  124,  126 
— ,  scarlet,  76 
— ,  swamp  white,  74 
— ,  white,  72 
— ,  yellow,  76 
Oaks  and  chestnut,  71 
Observations  about  trees,  general, 
235 

—  and  precision,  child  training  in, 

237 

Obtuse  leaf  Japanese  cypress,  123 
Opposite  branched  trees,  31 
Orange,  Osage,  105,  128 
Oriental  spruce,  122 

—  sycamore,  63,  123 
Osage  orange,  105,  128 
Ostrya  virginiana,  70 
Outdoor  lesson  on  trees,  234 
Oyster-shell  scale,  53 

Paper  birch,  66 
Picea  canadensis,  15 

—  excelsa,  13 

—  mariana,  15 

—  orientalis,  122 

—  parry  ana,  15 

—  pungens,  15,  123 
Pignut  hickory,  87 
Pin  oak,  79,  119,  125 
Pine,  Austrian,  9,  11,  122 
— ,  Bhotan,  6,  122 


Pine,  Mugho,  123 
— ,  red,  11,  126 
— ,  Scotch,  9,  11 
—  trees,  1 

—  weevil,  white,  4 
— ,  white,  122,  126 
Pines,  224 

Pinus  Austriaca,  9 

—  excelsa,  6 

—  mughus,  123 

—  resinosa,  11,  126 

—  rigida,  6 

—  strobus,  4,  122,  126 

—  sylvestris,  9 
Pitch  pine,  6 
Pith,  106 

Plane  or  sycamore  tree,  60 
Plant  lice,  or  aphides,  68,  152 

—  study,  value  of,  for  children, 

235 

—  trees,  how  to,  130 
Planting  forests,  179 

—  forests  with  seedling  trees,  189 
-  little  trees,  methods  of,  211 

— ,  improving  woodland  by,  207 

—  new  trees,  207 

—  trees,  128,  130 

—  most  economical  method,  211 

—  —  on    land     unsuitable    for 

crops,  207 
Plants,  adaptation  of,  to  seasonal 

changes,  238 
Platanus  occidentals,  60 

—  orientalis,  63,  123 
Polyporus  betulinus,  157 
Poplar,  balsam,  54 

— ,  Carolina,  51 

— ,  Lombardy  or  Italian,  51 

— ,  silver,  53 

— ,  tulip,  92 

— ,  white,  53 

— ,  yellow,  92,  231 

Populus  alba,  53 

—  balsam  if  era,  54 


INDEX 


249 


Populus  deltoides,  51 

—  grandidentata,  54 

—  nigra,  51,  128 

—  tremuloides,  54 
Pores  in  wood,  227 

—  small  or  indistinct,  230 

—  varying  in  size,  230 

Poster  for  private  woodlands,  215 
Precautions  against  fire,  214 
Protection     against     fungi     and 

insects,  196 
Pruning  forest  trees,  166 

—  lawn  trees,  166 

—  shade  trees,  166 
— ,  tools  used  in,  166 
— ,  too  severe,  163 

-  trees,  fundamental  principles, 

160 

time  for,  162 

Pussy  willow,  59 

Quaking  aspen,  54 

Quality  of  trees,  how  to  judge,  129 

Quality  of  wood,  how  to  judge, 

233 
Quercus  alba,  72 

-  palustris,  79,  119,  125 

—  platanoides,  74 

-  rubra,  76,  124,  126 

—  velutina,  75 

Red  cedar,  225 

—  and  arbor-vitse,  description 
of,  19 

-  gum,  95,  231 

—  horsechestnut,  34 

—  juniper,  22 

-  maple,  41,  120,  125 

—  mulberry,  105 

-  oak,  76,  124,  126 

-  pine,  11,  126 

—  or  black  oaks,  226 

—  or  sweet  gum,  231 


Red  spider,  13 
Redwood,  226 

Removal    of    dead    and    broken 
branches,  162 

—  of  trees,  how  to  mark,  212 
Requirements  of  trees,  110 
Retinospora  obtusa,  123 
Rhytisma  acerinum,  41 
Ring-porous  woods,  221,  226 
Robinia  pseudacacia,  100,  126 
Rock  maple,  38 

Roots,  110 

• — ,  development  of,  110 

— ,  protection  of,  from  drying,  130 

Rust,  apple,  22 

Safeguarding  forests,  179 

Salix  babylonica,  58 

Salix  discolor,  59 

Saperda  vestita,  98 

Sap-wood,  106 

Sawfly,  27 

Scale,  cottony-maple,  39 

— ,  oyster-shell,  53 

Scale-like  leaves,  19 

Scarlet  oak,  76 

Sciadopitys  verticillata,  123 

Scolytus  quadrispinosus,  85 

Scotch  pine,  9,  11 

Screening  trees,  128 

Season,  influence  of,  116 

Seasons  for  spraying  trees,  137 

Seedling    trees,    planting    forests 

with,  189 

Shade  trees,  pruning,  163 
Shagbark  hickory,  83 
Shellbark  hickory,  85 
Silver  maple,  38 

—  poplar,  53 
Soft  maple,  40 

—  pines,  224 

"  Softwoods  "  or  conifers,  224 
Soil  erosion,  forests  prevent,  187 
— ,  influence  of,  on  trees,  112 


250 


INDEX 


Soil  of  wooded  areas,  preserving, 
206 

— ,  physical  character  of,  import- 
ant for  production  of  trees, 
114 

Soulange's  magnolia,  121 

Specifications  for  street  tree,  131 

Specimens  of  wood,  how  to 
identify,  222 

Split  trees,  176 

Spray  trees,  how  to,  138 

Spraying  apparatus,  138 

—  foliage,  141 

—  for  caterpillars,  145 

—  for  fungous  diseases,  160 

—  material,  138 

arsenate  of  lead,  138 
kerosene  emulsion,  139 
lime-sulfur  wash,  139 
tobacco  water,  139 
whale-oil  soap,  139 

—  trees,  seasons  for,  137 

—  trees,  thoroughness   essential, 

138 

Spruce  and  hemlock,  descrip- 
tion of,  11 

— ,  black,  15 

— ,  blue,  123 

— ,  Oriental,  122 

— ,  Norway,  13 

— ,  white,  15 

Spruces,  224 

Star-shaped  leaves,  93 

Stem,  106 

Stomata,  117 

Streets,  trees  for,  123 

Structure  of  trees,  106 

—  of  woods,  217 
Sucking  insects,  4,  134 
Sugarberry,  71 
Sugar  maple,  37,  121 

—  maple  borer,  37 
Suggestions  for  forming  tree  clubs, 
242 


Suggestions  for  outdoor  study  of 
trees,  234 

—  for  planting  little  trees,  211 

—  for  safety  of  tree  climbers,  167 

—  for  tree  nursery,  132 
Surface  wounds,  168 
Swamp  maple,  43 

—  white  oak,  74 
Sweet  birch,  66 

—  gum,  93,  231 
Sycamore,  230 

—  maple,  44 

—  tree,  59,  60,  123,  230 

Tamarack,  29,  225 

Taxation,    forest    lands    exempt 

from,  216 

Taxodium  distichum,  30 
Taxus  baccata,  123 
Thuja  occidentalis,  22 
Tilia  americana,  95 

—  microphylla,  119 
Tobacco  water,  139 
Tools  used  in  pruning,  168 
Toxylon  pomiferum,  105,  128 
Training    a    child    to    recognize 

trees,  237 

—  children    in    observation    and 

precision,  237 
Trametes  pini,  27 
Treating  surface  wounds,  168 
Tree,  ailing,  how  to  tell  an,  153 

—  and  nature  study,  value  of,  235 
— ,  beech,  59,  128,  231 

— ,  birch,  59 

— ,  blue  beech,  59 

—  climbers,  suggestions  for  safety 

of,  167 

—  clubs,  suggestions  for  forming, 

242 
— ,  coffee,  120 

—  diseases,  153 

—  diseases,  effects  of,  as  destroy- 

ers and  upbuilders,  239 


INDEX 


251 


Tree   growth,   conditions  for,    in 

different  localities,  119 
— ,  hackberry,  59 
— ,  iron  wood,  59 
— ,  nettle,  71 

—  nursery,  suggestions  for,  132 
— ,  plane,  60 

—  repair,  168 

— ,  sycamore,  59,  230 

— ,  tulip,  126,  231 

— ,  weeping  willow,  46,  59 

Trees  and  character  building,  235 

— ,  care  of,  134 

— ,  care  to  be  exercised  in  location 

of,  130 

— ,  civic  lessons  reflected  in,  239 
— ,  community  life  of,  239 
— ,  coniferous,  122 
— ,  crowding,  203 
— ,  deciduous,  119 
— ,  effect  of  frost  on,  116 
— ,  effect  of  heat  on,  116 
— ,  enemies  of,  239 
--  for  lawns,  119 

—  for  screening,  128 

—  for  streets,  123 

—  for  woodland,  126 

— ,  general  observations  about, 
235 

— ,  hickories,  walnut,  and  butter- 
nut, 83 

—  how  to  identify,  1,  26,  83 
how  to  mark  for  removal,  212 
how  to  plant,  130 

how  to  spray,  138 
improperly  pruned,  161 
individuality  of  1,  182,  239 
influence  of  light  on,  114 
influence  of  moisture  on,  110 
influence  of  soil  on,  112 
insects  injurious  to,  134 
measuring  diameter  of,  183 
methods  of  planting  little,  211 
methods  of  removing,  212 


Trees,  nature  and  habits  of  indi- 
vidual, 185 

— ,  needs  that  nature  or  iran 
must  supply,  117 

— ,  outdoor  lesson  on,  234 

— ,  physical  character  of  soil 
important  for  production  of, 
114 

— ,  planting,  on  land  unsuitable 
for  crops,  207 

— ,  pruning,  fundamental  prin- 
ciples, 160 

— ,  — ,  how  to  cut  properly,  162 

— ,  quality,  129 

— ,  rapidity  of  growth  of  different 
species,  186 

— ,  requirements  of,  110 

— ,  seasons  for  spraying,  137 

— ,  setting,  130 

— ,  structure  of,  106 

— ,  study  of  rings  of  various 
species,  186 

— ,  suggestions  for  outdoor  study 
of,  234 

— ,  suggestions,  for  planting  little, 
211 

—  suitable  for  the  soil,   care  in 

selecting,  210 
— ,  tendency  to  split,  176 
— ,  thoroughness    essential    in 

spraying,  138 
— ,  time  for  pruning,  162 
—  told   by   their   their   bark    or 

trunk,  59 
— ,  training  a  child  to  recognize, 

237 
— ,  value  of,  as  health  givers  and 

moral  uplifters,  237 

—  what  to  plant  and  how,  119 
when  and  how  to  procure,  129 
when  to  plant,  129 

when  to  spray,  137 
wooded   areas    improved    by 
planting  new,  207 


252 


INDEX 


Trees,  yew,  57 

Tsuga  canadensis,  17,  128 

Tulip  poplar,  92 

—  tree,  90,  126,  231 
Tussock  moth,  143 

Ulmus  americana,   47,  119,  125, 
126 

—  campestris,  50 
Umbrella  pine,  Japanese,  123 

—  tree,  100 

Value  of  plant  study  for  children, 
235 

—  of  tree  and  nature  study,  235 

—  of  trees  as  health  givers  and 

moral  uplifters,  237 

Walnut,  83 

— ,  black,  87 

Wasteful  lumbering,  193 

Weeping  willow  tree,  46,  59 

Western  catalpa,  104 

Whale-oil  soap,  139 

White  ash,  35,  126,  227 

—  birch,  European,  68,  120 

—  cedar,  24 

—  elm,  50 

—  flowering  dogwood,  104 
Whiteheart  hickory,  87 
White  maple,  40 

—  mulberry,  105 

—  oak,  72 

—  oak,  swamp,  74 

• —  or  gray  birch,  64 

—  pine,  4,  122,  126, 

—  pine  weevil,  4 

—  poplar,  53 

—  spruce,  15 
Whitewood,  92,  98,  231 
Willow,  weeping,  58 
— ,  pussy,  59 

Wood,  diffuse-porous,  221,  230 
— ,  diseased,  disposal  of,  212 


Wood,  early,  220 

-  fibers,  222 

— ,  how  to  identify  specimens,  222 
— ,  how  to  judge  quality  of,  233 
— ,  late,  220 

—  medullary  rays,  220 

—  parenchyma,  222 

—  resin  ducts,  222 
— ,  ring-porous,  221 

—  spring,  220 

— ,  structure,  of,  217 

—  summer,  220 
Woodland,  care  of  the,  203 

—  how  to  improve  by  removing 

trees,  211 

—  how     to     judge,     unfavorable 

conditions,  203 

-  trees,  126 

Woodlands,  other  means  of  pro- 
tecting, 216 

Woodlot,  small  cost  of  well- 
selected  young  trees  for  the, 
208 

Wood,  structure  of,  217 

Wooded  areas  improved  by  plant- 
ing new  trees,  207 

—  areas,  preserving  soil  of,  206 
Woods,    identification,   properties 

and  uses  of  common,  217 
— ,  ring-porous,  221,  226 

—  with    large    and    conspicuous 

rays,  226 

—  with  pores,  226 

—  with  resin  ducst,  224 

—  with  small  and  inconspicuous 

rays,  227 

—  without  pores,  224 

—  without  resin  ducts,  225 
Wounds,  importance  of  covering, 

164 

— ,  methods  of  covering,  164 
— ,  treating  surface,  168 

Xerophytes,  111 


INDEX 


253 


Yellow  birch,  68 

—  locust,  101 

—  oak,  76 

-  poplar,  92,  231 
Yew,  English,  123 


Yew  trees,  57 

Young    trees    for   the    woodlot, 

small    cost    of  well-selected, 

208 


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